Adding support to ServiceManagement for role operations Reboot and Reima...

The service management API does not have support for all PaaS operations, RebootRole and ReimageRole being two that are missing and I require.  I modified ServiceManagementService.js and the corresponding ServiceManagementSerialize.js method to add support for both of these operations.  I also added an example test for this functionality.  I used RestartRole as an example for the code changes as well as test changes.