adding collections renderer

[mauricefallon]

This adds a renderer which can draw a variety of point clouds, primitive shapes and transform triads using messages transmitted from an external application.

Its actually a very mature interface that was well tested in the old GTK lcm viewer. Its similar in many ways to Markers in ROS:
http://wiki.ros.org/rviz/DisplayTypes/Marker

Its supports:

• individual or lists of triads, points, simple polygons, triangles etc.
• addition to or replacement of an entire collection e.g. adding a new triad to an existing collection of triads
• nesting of point clouds relative to transforms. This is useful for mapping applications as point clouds can be moved by changing the transform e.g. moving the frame of a LIDAR sensor to move the point cloud
• remote reset of the collection list
• vary the size and alpha of poses and objects
• dynamically populate the list of objects in the scene graph

Here are two rough videos. I'll submit a tutorial in time:

• a variety of features
• lists of triads being added to
• triads colored or typical rgb

Note: currently the collections lcmtypes are in a pod within pronto, but they could easily be ported to bot_core or an independent repo. collections is only built with the director application at present

[mauricefallon]

The original GTK rendering code is here and be melded for easy comparison. Changes are very minimal:
https://github.com/openhumanoids/pronto/blob/master/visualization/src/collections_renderer/collections_renderer.cpp