bug #879 csrf_protection is now under framework.form instead of framework (BenoitLeveque)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #879).

Discussion
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csrf_protection is now under framework.form instead of framework

Unrecognized option "csrf_protection" under "framework" was triggered when installing master version of this repository

Commits
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0daa8bc csrf_protection is now under framework.form instead of framework

Author: fabpot

app/config/config.yml

@@ -15,8 +15,8 @@ framework:
     router:
         resource: "%kernel.root_dir%/config/routing.yml"
         strict_requirements: ~
-    form:            ~
-    csrf_protection: ~
+    form:
+        csrf_protection: ~
     validation:      { enable_annotations: true }
     #serializer:      { enable_annotations: true }
     templating: