Updated ModelToIdPropertyTransformer so it works with Entities which implement \ArrayAccess
Added FooArrayAccess class to allow testing of new code
See #2301
Updated logic and added Exception messages when an incorrect configuration is used.
#1723 added prototype for code like ``` $formMapper ->with('tab1', array('tab'=>true)) ->with('group1') ->add('username') ->add('password') ->end() ->with('group2', array('collapsed' => true)) ->add('enabled') ->add('createdAt') ->end() ->end(); ```
fix
+ added tab support on edit page * fixed CS issues on BaseGroupedMapper.php
continue implementation of tab support
Fixed wrong handling _per_page and _page datagrid parameters in php 5.3
Merge pull request #2348 from pulzarraider/per_page_fix

Fixed wrong handling with _per_page and _page datagrid parameters in php 5.3
Add tip about 'required' in sonata_type_collection

Document 'required' option behavior in sonata_type_collection
Merge pull request #2302 from caponica/fix_transformer_array_access_entity

Fixed problem with ModelToIdPropertyTransformer and ArrayAccess entities
Pass admin through to autocompleteItems callback:
~ modified HelperController::retrieveAutocompleteItemsAction() to pass $targetAdmin through to callback instead of $datagrid
~ updated documentation of the callback
Fixed an issue with one to many relations

As described in #2325
Merge pull request #2353 from caponica/autocomplete_callback_with_admin_v2

Pass admin through to autocompleteItems callback:
Merge pull request #2351 from eikes/master

Add tip about 'required' in sonata_type_collection
Fix css - added scrollbar on list view for small screens
Autocomplete changes:
Removed initSelection method in favour of directly setting the initial value
Added extra (not null) check autocompleteInput onChange function (prevents error when first called)
Merge pull request #2169 from antoinemineau/master

Fix css of list box on small screens (added scrollbar)
Merge pull request #2326 from caponica/autocomplete_refactor_init

Refactored how the autocomplete initialises its values
Minor improvements in translation messages in sonata_type_model_autocomplete
Merge pull request #2363 from pulzarraider/autocomplete_msg_excp_impr

Minor improvements in translation messages in sonata_type_model_autocomplete