Fix #1689
Update delete.html.twig

1. Add "Back to List" button
2. Replace input type submit to button type submit with trash icon
3. Add class icon-white to the edit link
Merge pull request #1690 from dkorsak/patch-5

Update delete.html.twig
CRUDControllerTest: added test for editAction
Merge pull request #1691 from pulzarraider/crud_controller_test4

CRUDControllerTest: added test for editAction
typo in installation docs
File location added for admin class in documentation
Merge pull request #1693 from peterkokot/patch-docs-2

File location added for admin class in documentation
Merge pull request #1692 from peterkokot/patch-docs

Typo in installation docs
Merge remote-tracking branch 'sonata/master' into admin-names