add pg_strom.debug_cuda_enable_coredump_on_exception for GPU kernel d…

…ebug

code cleanup of float2.c

update changelog

Merge branch 'master' of github.com:heterodb/pg-strom

bugfix: partition-wise GpuJoin made wrong AppendPath

Prior to this commit, try_add_gpujoin_paths() overwrite 'outer_path'
variable if outer_path is GpuJoinPath and expandable.
Then, it also called try_add_gpujoin_append_paths with modified
'outer_path', in the result, sub-path of AppendPath has wrong
relids and failed to run any more.

add alternative pg_*printf() for build of mysql2arrow

mark as v2.2 milestone

update CHANGELOG

fix uninitialized veriables