When emptying TeamAdminService collections also drop the form fieldset
(necessary to complete the GH-15 hack in this case)
Temporarily disable unique constraints on elements in Collections
(Doctrine inserts before deleting when persisting collections, causing constraint violations)
Simplify the process of configuring filtering of ObjectSelect elements
 - Override Doctrine's ObjectSelect to add a proxy nuker
 - Add service extensions to inject updated find method configurations where appropriate
Add service extension to automatically lock a finished match when all signatures are in place
Fix bug in HideStatusAndLockedFieldsWhenCreatingNewMatch service extension
(Was not hiding status and locked fields when creating new match)
Fix a few visual niggles with the display of signatures when the match is locked
Typo that was causing the Home and Away select boxes to list the same players