Updated the Mambu Models jar for V3.7 to include Activity data fields
Merge https://github.com/mambu-gmbh/Mambu-APIs-Java
Refactored remaining Services. Added 3.7 APIs

1. Updated code based on the refactoring check in review comments
Main changes include:
- Added ApiType constructors
- Changed account specific ApiTypes into generic ones
- Renamed: operation -> action
- ServicesHelper changes:
  Replaced Object with generic types.  This eliminates the need for
casting as well as for Suppressing warnings in Service classes
Implemented other suggestions: static map replaces ‘if’ statements for
type collections

2. Refactored all Services to use ApiDefintion and ServiceHelper
3. Fixed test cases as needed
4. Added DemoTestIntelligenceService

5. Implemented wrappers for Mambu 3.7 API additions:
5.1. Updated Maven’s pom to build Mambu-APIs-Java-3.7-bin.jar using
mambu-models-V3.7.jar
5.2 MBU-4607 - As a Developer, I'd like to work with Custom Views
a) added getting Custom Views API wrapper
b) added filtering Clients/Groups/Loans/Savings by custom view ID
5.3  MBU-5946 - As a Developer, I'd like to filter lists on centres via
API
Updated wrappers to filter by centreId for Clients/Groups/Loans/Savings
Services