Fixes #2688
Add ability to set X Frame Option header per page
Allows default X Frame Options value to be set in settings file.
Add caching to Page.get_xframe_options
Add cache clearing to Page model unit tests
Merge pull request #2689 from jrief/fix-issue-2688

Fixes #2688
Merge pull request #2477 from xray7224/XFrameOptions

Per-page X-Frame-Options/Clickjacking protection
renamed migration
#2679 fix for cms3
Merge pull request #2692 from FinalAngel/develop

#2679 fix for cms3
And yet another missing unlocalized
tree tooltip change to be more responsive and awesome. Fixes #2678 and #2677
fix typo
fixed an issue where element is not opened on the top frame
Merge pull request #2695 from FinalAngel/develop

tree tooltip change to be more responsive and awesome
Merge pull request #2694 from jrief/fix-issue-2688

And yet another missing unlocalized