BUG Don't sort when deleting records in ManyManyList::removeAll()

This breaks databases like MSSQL which don't allow an ORDER BY with
a subquery at the same time. DELETE queries don't need to be ordered,
so we can safely remove the default.
API: Move LimitWordCount() to Varchar
Update controller.md
Merge pull request #1719 from wilr/open5793

API: Move LimitWordCount() to Varchar
Fixed extra_requirements docs