[actuator/waypoint] not active if no new goal

fix #416 was interfering other motion actuator.
[camera] fix orientation

Thanks to Lars Kunze for repporting on the mailing list.

ROS conventions suggest a coordinate frame for camera as follows:
(cf. http://www.ros.org/reps/rep-0103.html#coordinate-frame-conventions)

z forward
x right
y down
Fixed depth camera orientation (thanks to Pierrick Koch)

ROS conventions suggest a coordinate frame for camera as follows:
(cf. http://www.ros.org/reps/rep-0103.html#coordinate-frame-conventions)

z forward
x right
y down

This solves issue #39

Merge remote-tracking branch 'pierriko/master'
Merge branch 'master' of https://github.com/strands-project/morse
Merge pull request #4 from kunzel/master

Fixed depth camera orientation