Fix unlink() for CacheEngine::clear() failed on windows.
Fixing some errors related to unlink() on windows
Update bakeshell so `bake all` gets the correct connection name.

Fixes #3972
Merge pull request #1497 from hiromi2424/fix-unlink-windows

Fix unlink() for CacheEngine::clear() failed on windows.

Refs #3930
Allow setting path constants in app/Console/cake.php as you can in webroot/index.php
Merge pull request #1507 from ADmad/2.3-console-constants

Allow setting path constants in app/Console/cake.php as you can in webro...
Update version number to 2.3.9