rtt_rosclock: added missing <string> include directive
rtt_ros_comm: do not latch topics by default

Signed-off-by: Ruben Smits <ruben.smits@intermodalics.eu>
rtt_ros_comm: it's cp.init, not cp.init_connection

Signed-off-by: Ruben Smits <ruben.smits@intermodalics.eu>
rtt_ros_integration: removed rtt_kdl_conversions from metapackage
rtt_ros_tests/rtt_rospack_tests: fixed tests for rtt_rospack due to changed service name (see 5b91757)
rtt_ros: added missing dependency to package roslib
rtt_rosclock: added cleanup function to terminate SimClockThread when the application quits

If the SimClockThread is not destroyed by the StartStopManager before the Logger is finally destroyed in __os_exit(),
RTT will restart the Logger due to log output in the RTT::os::Thread::~Thread() destructor and overwrite the orocos.log file.
rtt_rosclock: fixed header installation directory