Added groundwork for OLAListener tests
Refactored olalistener methods
Moved SelectServer and OlaClient imports to application level
Added tests for OLAListener
Added static methods for safe mock OLA object creation
Refactored olalistener methods into nested lambdas for callback handling
Added event-based thread termination for olalistener
Improved selectserver and olaclient mocks
Merge branch 'issue/3'