Fixed edge case which allowed login with empty password.

Ensure skipping call to FormAuthenticate::_checkFields() does not allow
logging in with empty password. Closes #2441.
Merge pull request #2444 from ADmad/2.4-auth-finduser

Fixed edge case which allowed login with empty password.
Fiexed error in CakeSession that would call start() in an infinite loop
when the session is marked as invalid
Add test to prove issues with deleteAll with $order set
Set 'order' to false to prevent issues with postgres

See: https://github.com/cakephp/cakephp/pull/2421#issuecomment-30074971
Ensuring session is configured before trying to destory it
Merge pull request #2450 from rchavik/2.4-delete-all-regression

2.4 delete all regression
Fixed failing test
Attempt to fix errors with postgres tests.
Change quotes to keep postgres happy.
Merge pull request #2449 from cakephp/fix-session-cyclic-error

Fixed error in CakeSession that would call start() in an infinite loop