Refactor emrapi module's ConditionService to use new functionality

Refactor emrapi module's ConditionService to use this new functionality under the hood (e.g. either delegating to openmrs-core, or using the current emrapi approach, depending on the openmrs-core version)

The source of the module can be found at https://github.com/openmrs/openmrs-module-emrapi

Take a look at https://wiki.openmrs.org/display/docs/Supporting+different+OpenMRS+versions

Now create a ConditionServiceImpl class in the new api-2.2 sub module.
This class should implement the org.openmrs.module.emrapi.conditionslist.ConditionService interface and delegate these calls to the openmrs-core ConditionService implementation.