provide template method to override controller creation
init needs to be called before initDefault
initialize Maps in constructor
returns new instance every time
make sure initialized is true after init()
added additonalProperties
if schema loading fails, then use fallbackSchema
use fallback schema if schema does not provide attributes for id and type
mke null safe
null safe
required needs to be false
fix error handling
expand null check to undefined as well
oldValue was changed when toggling null checkbox