Merge pull request #2194 from sbussetti/develop

This adds a basic freeform ability to mark Plugins as "child_only" and optionally, who can be its Parents
two test fixes

* Don't show log output in the tests
* Fixed default config to not trigger DeprecationWarning
Merge pull request #2200 from ojii/develop

two test fixes
Use page.pk instead of hardcoded Id
Don't rescan_placeholders when loading fixtures, Fixes #1031
add a new test for fixture loading
Merge pull request #2201 from yakky/feature/micro_test_fix

Use page.pk instead of hardcoded Id
Different testing strategies to overcome the problems of json fixtures in tests
Test cleanup. Comments added.
Merge pull request #2202 from yakky/feature/fixture_loading

Reworked fix for fixture loading
Fix typo in CMS_LANGUAGES validation logic.
Merge pull request #2204 from mpaolini/conf_typo

Fix typo in CMS_LANGUAGES validation logic.
First implementation of frontend-editable models
Add language
Better language handling
Remove debug from template
Test WiP
Fix placeholder tests
Documentation WiP
Add callable as allowed item target