adds caching to normal placeholders and optimizes imports for debugtoolbar cache panel
fixed tests
docs
cache views
Merge branch 'develop' into fix-2267

Conflicts:
	cms/tests/admin.py
	cms/views.py
caching for views.py
docs
do not cache pages for logged in users
test caching of placeholders
Add missing unlocalize filters
Merge pull request #2699 from jrief/fix-issue-2688

Add missing unlocalize filters
Add PAGE_TEMPLATE variable to context
Add upgrade notes for cms.context_processors.media
Add documentation for PAGE_TEMPLATE. Reorganize app_integration.rst.
Refactor PAGE_TEMPLATE as lazy object
Rename PAGE_TEMPLATE to CMS_PAGE_TEMPLATE
Really lazy implementation
Add test with queries number assertion for cms.context_processors.cms_settings and cms.middleware.page
Rename CMS_PAGE_TEMPLATE to CMS_TEMPLATE
Fix documentation