Tracker #34010 fix

Fix Frontend image upload with languagefilter plugin enabled by also ignoring POST requests where only FILES variables are present.
Adding cases to emailcloak
[fix] Address issues with current PHP 5.6 RC. Fixes #3961

Add PHP 5.6 to Travis config

Add PHP 5.6 to skipped tests with unserialize issues
Merge pull request #4069 from infograf768/mailcloaknewcases

Regression: Adding cases to emailcloak
( ! ) Parse error: syntax error, unexpected 'endif' (T_ENDIF) in
ROOT/administrator/modules/mod_feed/tmpl/default.php on line 111
Merge pull request #4049 from osignell/staging

Tracker #34010 fix
Merge remote-tracking branch 'upstream/staging' into nestedmodels