Migration for FamilyInstanceParameterSelector & FamilyInstanceParameterG...

...etter

- Implements FamilyInstanceParameters class to get the dropdown for all
the family instance as well as type parameters.
- Provide migration logic for FamilyInstanceParameterSelector &
FamilyInstanceParameterGetter
- Fixes http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-2638
- Fixes http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-2660
- Fixes http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-2334