Adding a dynamic library for system-wide hourglass support

 * A dynamic c++ library provides entry points to show/hide app startup mouse cursor
 * simple python app to show how to use it
 * needs more testing, installation, and refactoring kdesk to use it
Improve python test app usage clarity
Adding a sample c++ test program to use the hourglass library
Providing an application name so the hourglass follows it

 * An application name is given to the "start" funcion
 * Startup notify will automatically stop the hourglass when the app comes responsive
 * Updated python and c++ tests for this feature
Adding hourglass lib to the build / installation chain
Merge pull request #76 from KanoComputing/shared-hourglass

system-wide hourglass support in a dynamic library