FLUID-4939: test case

Added a test case which demonstrates the init functions being executed multiple times when a gradeName is added during instantiation.
FLUID-4939: Corrected double merging of own default options introduced by fix to FLUID-4937
Merge remote-tracking branch 'amb26/FLUID-4939'

* amb26/FLUID-4939:
  FLUID-4939: Corrected double merging of own default options introduced by fix to FLUID-4937
  FLUID-4939: test case