More changes to log messages
OPEN - task 1: Improve the messages stored by the Actions Log 
http://github.com/fserena/GLORIAServices/issues/issue/1

RTSHandler exception messages adapted to URL format.
ExperimentBooker timeslot length setup (again :S) to 15 minutes.
UserRepository, ExperimentExecutor and ImageRepository log messages
improved.
OPEN - task 1: Improve the messages stored by the Actions Log 
http://github.com/fserena/GLORIAServices/issues/issue/1

Teleoperation services updated (log improvements - Removed exceptions
class name)
Merge pull request #13 from fserena/logenhancement

Logenhancement