added encounterTypeList and formList properties
added unit test for restricting by encounterType and unit test for restricting by form
placed the tests for restricting by encounterType and by form into  separate unit test methods (evaluate_shouldLimitObsByEncounterType() and evaluate_shouldLimitObsByForm())
Merge pull request #40 from rubailly/master

added evaluate_shouldLimitObsByEncounterType() and evaluate_shouldLimitObsByForm() test methods