Changed sample user name

Changed from keving to kgarwood
Changed references to gender to sex
Added static singleton method

ProductionRIFStudyServiceBundle now manages a singleton instance which
is created in the declaration of a static variable.
Renamed methods to be more meaningful
Changes due to renamed methods

Changed the rif job submission service api from having
"getImmediateSubTerms" to "getImmediateChildHealthCodes"
Renaming "RIFJobSubmission" to "RIFStudySubmission"

Changing the names of classes to make more sense.  Job sounds too
technical whereas study is something people could more easily relate to.
Isolate shared interface methods

Introducing "RIFStudyServiceAPI" to define the method definitions that
are common to the RIFStudySubmissionAPI and the
RIFStudyResultRetrievalAPI.
Moving AgeGroupSortingOption enum from API

Previously, the AgeGroupSortingOption enum has been defined within the
definition of the APIs.  Both the RIFStudySubmissionAPI and the
RIFStudyResultRetrievalAPI have this enum defined so it makes sense to
extract the common enum.  I could have put the common definition into
the RIFStudyServiceAPI interface but I thought it was better to isolate
it as its own independent enumeration.
Adding proxies to support getCalculationsMethod()

Added classes that are used to help convert data from a
CalculationMethod into a JSON stream
Introducing Study Result Retrieval Context

Adding a new class to reduce the number of parameters that are often
passed to methods for the RIFStudyResultRetrievalAPI
Removed final references from interface methods

Mainly for the convenience of copying and pasting into an
implementation, I put 'final' in front of method parameters.  I've now
changed this because it adds no value to the interface itself.
Incorporated StudyResultRetrievalContext

Modified some method signatures to use the new class
StudyResultRetrievalContext instead of a cluster of three common
parameters: geography, geoLevelSelect and studyID
Merge branch 'master' of https://github.com/smallAreaHealthStatisticsUnit/rapidInquiryFacility