Initial version of notification added.
Merge remote-tracking branch 'origin/master' into email-is-sent-when-new-post-in-group

Conflicts:
	composer.json
	composer.lock
	src/Cobase/AppBundle/Controller/BaseController.php
	src/Cobase/AppBundle/Controller/GroupController.php
Removed invalid code (copy-paste from some other project)
Fixed invalid DI service settings. Now it is possible to select a group that you want to be notified of new posts (also unnotify feature)
Changed method signature
Added PostEvent entity + migrations
renamed methods. Added newPostAdded() method
Now a notification email is sent to those who wish to get one when a new psot is made (partially done)
Updated email template. Added migrations.
fixed incorrect test
Added a command for sending notifications
Fixed test group name
updated installation manual
added some missing parameters
moar parameter fixes
Merge remote-tracking branch 'origin' into email-is-sent-when-new-post-in-group

Conflicts:
	app/config/parameters.yml-dist
	composer.lock
	src/Cobase/AppBundle/Controller/BaseController.php
Removed php 5.4 specific code
even moar fixes
Fixed variable name that shadowed another variable with the same name
Fixed merge conflicts