Acl: Add hasAndBelongsToMany to AclPermission

Fixes #373
fixes set default language to english for all tests
Acl: Fix broken test due to invalid return value in Auth::user()

This issue became apparent after a recent commit in
cakephp/cakephp@82d57fb8b2d194b0bfdbbe6ecb7e974615c9cc7b
Acl: Fix duplicate values returned by getAllowedActionsByUserId()
Acl: Fix warnings displayed due to invalid aros_acos

Closes #386
CS Fixes
Merge remote-tracking branch 'upstream/1.5' into 1.5