* 12826 add RackType
* 12826 add forms, filters, tables
* 12826 add to menu
* 12826 remove role
* 12826 add api/serializers
* 12826 add tests and fixes
* 12826 fix tests
* 12826 fix tests
* 12826 fix tests
* 12826 fix tests
* 12826 add device_type to device and instantiation
* 12826 test device creation
* 12826 add slug
* 12826 fix tests
* 12826 fix slug field
* 12826 prevent modification of rack fields if rack_type set
* 12826 update rack fields on rack_type edit
* Misc cleanup
* Update model docs
* Add manufacturer field to RackType
* Add test for mounting_depth
* Rename 'type' to 'form_factor'
* Create base classes for Rack & RackType models, serializers
* Hide RackType-defined fields on RackForm when a rack type is set
* Establish a base filter form for Rack & RackType
* Clean up RackType attr inheritance
* Clean up templates
---------
Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>
