Made apischema a bit less restrictive.

All additionalProperties are now True instead of False
All array minsizes are now 0 instead of 1
Create Instance now has an additional service_type optional property

fixes bug #1215183
fixes bug #1218661
fixes bug #1218662

Change-Id: If5c9344464a730220a588294383bb473e7bc5e7c
Merge "Made apischema a bit less restrictive."