Merge branch 'docs-prot-branches-mpenna20190906' into 'master'

Docs: Clarified wording to match Permissions doc

See merge request gitlab-org/gitlab-ce!32786

doc/user/project/protected_branches.md

@@ -5,9 +5,8 @@ type: reference, howto
 # Protected Branches
 [Permissions](../permissions.md) in GitLab are fundamentally defined around the
-idea of having read or write permission to the repository and branches. To
-prevent people from messing with history or pushing code without review, we've
-created protected branches.
+idea of having read or write permission to the repository and branches. To impose
+further restrictions on certain branches, they can be protected.
 ## Overview