Merge branch '3.x' into 3.next

Fix command name. (#1082)

As seen in the default value for `BaseCommand::$name` and asserted
in `BaseCommand::setName()`, the command names need a "root" part
which is usually "cake".

Fix singular/plural variable collision in baked templates (#1075)

* Fix singular/plural variable collision in baked templates

When baking templates for models where the singular and plural forms are
identical (e.g., "news", "sheep", "fish"), the generated foreach loops
would incorrectly use the same variable for both the collection and the
iteration variable, producing invalid code like:

    foreach ($news as $news):

This fix appends "Item" to the singular variable name when a collision
is detected, producing valid code:

    foreach ($news as $newsItem):

Refs https://discourse.cakephp.org/t/paginator-error/12806/4

* Fix additional singular/plural variable collisions

- Change suffix from 'Item' to 'Entity' (less likely to collide with
  model names like 'NewsItem')
- Add same fix to ControllerCommand for controller action generation
- Add collision detection in view.twig for related entity loops
  (appends 'Related' suffix when otherSingularVar matches singularVar)
- Add collision detection in Controller/add.twig and edit.twig for
  association list variables (appends 'List' suffix when otherPlural
  matches singularName)
- Add test for ControllerCommand singular/plural collision handling

Merge pull request #1072 from cakephp/issue-1071

Fix path check on Windows.

Merge pull request #1070 from othercorey/patch-1

Fix checking references int non-foreign constraints

Merge pull request #1068 from cakephp/composite-unique-messages

Add descriptive error messages for composite unique constraints

Merge pull request #1061 from cakephp/bump-twig-view-constraint

Bump twig-view constraint

Merge branch '3.next' into 3.x

Merge pull request #1042 from cakephp/3.x-uses-to-link

Use link instead of uses to avoid PHPUnit clash.

Update composer.json