Create ConditionService implementation

Create an implementation of the ConditionService interface, named ConditionServiceImpl

ConditionServiceImpl copied from https://github.com/openmrs/openmrs-module-emrapi/blob/9257dcd31d4d7af72742e78337662988b1edb463/condition-list/src/main/java/org/openmrs/module/emrapi/conditionslist/impl/ConditionServiceImpl.java

ConditionServiceTest copied from https://github.com/openmrs/openmrs-module-emrapi/blob/9e184120c95d027aab5f58fda5deeeab5ff62d0d/condition-list/src/test/java/org/openmrs/module/emrapi/conditionslist/impl/ConditionServiceImplTest.java

You then need to add the service to the applicationContext-service.xml spring configuration file