Fix fcl dependency in CMakeLists.txt

See http://answers.ros.org/question/80936 for details

Interestingly collision_detection_fcl already uses the correct
variable ${LIBFCL_LIBRARIES} although it wasn't even set before. :-)
resolve full path of fcl library

Because it seems to be common practice to ignore ${catkin_LIBRARY_DIRS}
it's more easy to resolve the full library path here instead.
Added doxygen for RobotState::attachBody() warning of danger.
Fixed asymmetry between planning scene read and write.
Improved error output for state converstion
Merge pull request #142 from ros-planning/attached-body-dox

Added doxygen for RobotState::attachBody() warning of danger.
Merge pull request #148 from davetcoleman/robot_state_error_msg

Improved error output for state conversion
Merge pull request #144 from ros-planning/read-planning-scene-fix

Fixed asymmetry between planning scene read and write.
Merge pull request #140 from v4hn/fix-libfcl-include

Fix fcl dependency in CMakeLists.txt
Merge branches 'hydro-devel' and 'dont-crash-non-chains' of https://github.com/ros-planning/moveit_core into hydro-devel