Vifm v0.12

New version makes textual preview asynchronous, provides support for 24-bit
colors, improves tree-view and introduces experimental Lua plugins support.

Thanks to everyone who tried out the beta.

Main changes:
 - color schemes and preview now support 24-bit colors;
 - depth of tree-view can now be limited and directories in it can be folded;
 - textual preview of files is now done asynchronously;
 - list of files can now be directly piped to programs via new macros;
 - external editing now asks for a re-edit after a failure;
 - status line can now take up several lines;
 - new keys for controlling viewer while in view mode;
 - view column separators;
 - Vifm has received a more advanced, but currently experimental, extension
   interface in a form of Lua plugins;
 - new logo.

More detailed list of changes.

Core:
 - added experimental Lua plugins support;
 - added interactive re-editing of file names in external editor.  Format now
   supports comments for displaying last error and original file names (thanks
   to Jose Riha, a.k.a. jose1711 and Diogo Lemos (a.k.a. dmlemos));
 - started using quickview's cache in view mode;
 - extended cache of viewer's output to contain multiple entries (initial
   version of the cache was added to skip redrawing graphics);
 - run background programs detached from a terminal (thanks to Miguel Madrid
   Mencía, a.k.a. mimame).

File operations:
 - added periodic forced flushing of data on copying data when 'syscalls' is set
   (thanks to Matthias Braun, a.k.a. mb720).

Invocation:
 - don't list inaccessible instances on --server-list.

Important fixes:
 - fixed losing files as a result of executing ":copy! &" or ":move! &" when
   both panes show the same directory (thanks to Hans Bieshaar);
 - fixed copying of executable files not working on FreeBSD (thanks to
   makijato);
 - fixed inability to map escape sequences due to extended keys in terminfo
   database (patch by M Kelly);
 - fixed hang on using previewer that takes over control over the terminal (like
   7z does to read password) (thanks to PRESFIL);
 - fixed vifm-convert-dircolors dropping copies of entries that differ only by
   case (thanks to flux242).

Normal and visual modes:
 - added zx normal mode key to fold/unfold directories in tree views.  The
   implementation is not optimal at this moment though (thanks to filterfalse,
   Ben Lu, a.k.a. ayroblu, RR0925 and Alexandre Viau).

Key bindings:
 - added a and A view mode keys that switch to next and previous viewer of
   current file correspondingly (thanks to j-xella);
 - added i view mode key that toggles raw mode (ignoring of defined viewers)
   (thanks to j-xella).

Command-line mode:
 - added :plugins command that opens plugins menu;
 - added :plugin command that manages plugins;
 - added :st[op] command what behaves like Ctrl-Z.  It's to be used in mappings
   (thanks to GummyGun);
 - added "depth=N" parameter to the :tree command (thanks to filterfalse);
 - added "combine" pseudo-attribute to "cterm" parameter of :highlight command.
   It changes behaviour from overwriting attributes of a parent highlight group
   (within their hierarchy) to appending to it (thanks to Andrew Savchenko);
 - added "gui", "guifg" and "guibg" parameters to :highlight command;
 - added network mount and `subst` targets to :volumes menu (patch by Phil
   Runninger);
 - made :compare obey file name filters (patch by qsmodo);
 - allow user-defined commands to include numbers in their names (thanks to
   anonymous at Vifm Q2A site).

:set command and options:
 - added %P macro to 'rulerformat' (and thus to 'statusline'), which expands to
   All, Top, xx% or Bot to indicate position within the view (thanks to
   iSeeU816);
 - added 'previewoptions' option to allow tweaking graphics preview a bit
   (thanks to Joshua Jensch, a.k.a., patroclos and flux242);
 - added "toptreestats" value to 'previewoptions' option, which makes stats
   appear before the tree (patch by qsmodo);
 - added literal values to 'viewcolumns' option (thanks to Jose Riha, a.k.a.
   jose1711, chelovechishko, DieSpinne and rwtallant13);
 - added %N macro to 'statusline' option, which adds a line break and increases
   height of the status line (thanks to Jose Riha, a.k.a. jose1711, qsmodo and
   jcarreja);
 - added "l" and "r" flags to the 'tuioptions' option.  It controls truncation
   of view titles (patch by qsmodo);
 - added %c 'statusline' macro that displays size of current file-system (thanks
   to Jose Riha, a.k.a. jose1711).

Macros:
 - added %Pl and %Pz macros for redirecting list of files to standard input of
   commands (thanks to PRESFIL);
 - added %v macro for vertical splitting in terminal multiplexers (patch by
   qsmodo).

File preview:
 - allow exploring empty files or output of viewers (thanks to Andrew
   Savchenko);
 - implemented asynchronous previewing for textual and pass-through (think
   sixel) viewers (thanks to StillSteal, laur89, Joshua Jensch, a.k.a. patroclos
   and p-kolacz);
 - detect broken links on preview and report them as such.

Color schemes:
 - changed semantics of light* color groups to add bold attribute only for
   terminals with less than 16 colors.  Aligns the behaviour with Vim.  Affects
   you only if you relied on that implicit bold attribute (thanks to Jose Riha,
   a.k.a. jose1711).

Menus and dialogs:
 - added shortcuts for toggling flags in permissions dialog on *nix (patch by
   qsmodo);
 - added some additional information about instance to the :version/:vifm menu;
 - made contents of map menus easier to comprehend by adding captions;
 - include shortcut prefix in title of map menus;
 - always display UID/GID in numeric form in File Info dialog (in parenthesis if
   the id was resolved to a string).

TUI (Text User Interface):
 - added support for direct/"true"/24-bit colors for ncurses 6.0 or later
   (thanks to Anton Kochkov, a.k.a. XVilka and IvanBarsukov);
 - added progress indication to the ruler of the view mode (corresponds to new
   %P macro of 'rulerformat') (thanks to iSeeU816).

Documentation:
 - document how %i macro affects background jobs.

Only on Windows:
 - fixed :goto not working with backslashes (thanks to Grueslayer);
 - fixed processing of keypad keys (thanks to Roland);
 - fixed :empty leaving empty directories (thanks to Grueslayer).

Packaging:
 - made it possible to build AppImage for Vifm (patch by michaellee8);
 - fixed running tests as root user (thanks to Michka Popoff, a.k.a. iMichka);
 - fixed an issue with packaging on one system (Linux in this case) and
   building on the other (OS X) (thanks to chenrui333).

Vim-plugin:
 - made :VifmCs of the plugin handle 24-bit colors.

Other changes:
 - updated logo of the project (thanks to Hescalalu for making it).

See change log for the full list of changes and by whom they were suggested or
implemented.