First pass demo

This completes a first pass of a demo.
Unfortunately I didn't get around to documenting the installation of the server-side parts of it, so for the time being it only runs on my computer, or in the computer of other really crafty people who can work with undocumented code.

The demo looks acceptably non-ugly and allows a user to plan random trajectories with a PR2 robot in empty space. The planning will return success / failure and in case of success it will actually show the trajectory by moving the robot to the desired pose going through all the planned waypoints. It looks pretty nice.

Some of the higher level next-steps, to be rendered as issues:
- Fix planning: right now target pose is for the wrist, not the tip of the EEF
- Allow choosing the planning group from the Web interface
- Allow choosing from a selection of different robots
- Allow uploading a new robot
- Add objects to the scene
- Save / share / aggregate results (crowdsourced motion planning)
- Document installation
- Deploy on the cloud