Allow third party developers to modify redirects

Changing the event allows third party developers to use the `redirect_to` value for additional processing
Fixes for Files module admin controller

Allow to create, rename and delete files/folders
Merge pull request #3240 from chrisdkemper/2.3/develop

Allow third party developers to modify redirects
Merge pull request #3242 from websemantics/2.3/develop

Nice work!
Removed the forbidden is_ migration
Merge branch '2.3/develop' of github.com:pyrocms/pyrocms into 2.3/develop
Migration is now 140
isLocked - is_ is IN
isHidden - IS IS IS
is_required rather than required
is_unique rather than unique
This is different
This is not nearly as useful as it was before streams evolved
Fix settings
Fix prefix here
Parse relations too
Fixed relational parsing in buttons so this can be fixed now
Fix users form
We don't need these anymore
No need for this anymore