[forms] the last touch: handle inlined relation forms as fields
by introducing a simple InlinedRelationField. This makese things
more flexible while removing a lost of overriding necessary.
sync_schema_props_perms('state_of')
sync_schema_props_perms('transition_of')
for etype in ('State', 'BaseTransition', 'Transition', 'WorkflowTransition'):
sync_schema_props_perms((etype, 'name', 'String'))