Migrate new app settings to AppFramework

Let's migrate those two new files.
disable database migration unit tests for MSSQL
Setting moment locale based on user selection
Add \OC\TempManager to handle creating and cleaning temporary files
Use the TempManager to handle temporary files
Use function outside of loop

Otherwise the function is executed n times which is a lot of overhead
Merge pull request #11752 from owncloud/use-function-outside-of-loop

Use function outside of loop
Add type hinting to functions

It's only reasonable to have proper type hinting here which might even help us to catch bugs.
Merge pull request #11735 from owncloud/mssql-migrations-master

disable database migration unit tests for MSSQL
Fix PHPDoc and remove explicit type hint
Generate stable etags for local files
Add missing DB rollback functionality
Merge pull request #11709 from owncloud/temp-handling

Cleanup handling of temporary files
Merge pull request #11767 from danbartram/add_db_rollback

Add missing DB rollback functionality
[tx-robot] updated from transifex
drop unneeded hint
Merge pull request #11760 from owncloud/add-type-hints-where-sensible

Add type hinting to functions
[tx-robot] updated from transifex
[tx-robot] updated from transifex
Merge pull request #11708 from owncloud/fix-momentjs

Setting moment locale based on user selection