bug with variable widget_type

Variable “widget_type” does not exist in SonataAdminBundle:Form:filter_admin_fields.html.twig
* http://stackoverflow.com/questions/23004015/variable-widget-type-does-not-exist-in-sonataadminbundleformfilter-admin-fie

* http://stackoverflow.com/questions/22985378/sonata-admin-filters-should-looks-like-set-of-checkboxes-but-got-error
Always add 'form-control' class to select boxes
ListMapper::addIdentifier() working when user is only granetd for "VIEW" action.
Merge pull request #2168 from phansys/master

ListMapper::addIdentifier() working when user is only granted for "VIEW"
Update composer.json

Update twig requirement to 1.15 to support round filter used in https://github.com/sonata-project/SonataAdminBundle/blob/453c87199286d30f4918a06a2665ecbc7ed1e2b6/Resources/views/Core/add_block.html.twig#L3
Merge pull request #2170 from lucasgranberg/patch-1

Update composer.json
Fix create_button.html.twig for subclass

Button group in dropdown is not a good idea ;)
Instead add an item for each subclass grouped by divider
Merge pull request #2172 from netounet/patch-1

Fix create_button.html.twig for subclass
remove IDE / OS specific ignore rules

These have nothing to do in a repository, they should be ignored
globally. What if everyone does the same with their custom IDE / OS ?
Added user permissions check

Added isGranted to check if a user has the right permissions, otherwise hide the affected button.

e.g.: Check if user has list permissions, otherwise don't show update and return to list button
Merge pull request #2182 from NoScopie/patch-3

Added user permissions check
Merge pull request #2145 from patrickli/select2-width

Always add 'form-control' class to select boxes
Fix AdminLTE http/https reference
deleteAction should use redirectTo to determine redirect url for easy
overriding.
Merge pull request #2180 from VermontDesignWorks/use_redirect_to_in_delete_action

deleteAction should use redirectTo to determine redirect url for easy overriding.
Update SonataAdminBundle.nl.xliff

Added missing Dutch translations.
Merge pull request #2193 from NoScopie/patch-5

Update SonataAdminBundle.nl.xliff
Wrong target file

Wrong target file
fix typo
Merge pull request #2202 from lowki93/documentation_improvements

fix typo