Fix 3.0 erroneous merge
Revert "Fix 3.0 erroneous merge"

This reverts commit a44e82b76f38917a535d3537da798bc6b268ce3a.
Improved EntryModelGenerator
Compile relations to the model
Fix array to string conversion error
We don't need static cache here
Add the Data folder to the installer writable folder list
Tweak these relationship FTs
Add static back in

This should work just fine now that relationships live in the models.
This needs to be an array
Check these in case they don't exist
Don't need require columns anymore - if so - rebuild
Improve relation FT
Implement new relation logic
Added getRelation convenience method
Fallback based on stream choice - this will prevent us from having to modify the parameters for relationship ft
As long as it's set
Merge branch 'refs/heads/2.3/develop' into 3.0/develop

Conflicts:
	system/cms/modules/streams_core/field_types/relationship/src/Pyro/FieldType/Relationship.php
	system/cms/modules/streams_core/field_types/user/src/Pyro/FieldType/User.php
	system/cms/modules/streams_core/src/Pyro/Module/Streams_core/AbstractFieldType.php
	system/cms/modules/streams_core/src/Pyro/Module/Streams_core/StreamModel.php