full EKF (ie, 7IMU/LED pairs) implemented and tested.

Plot overhead view (z axis not represented) of data
for 7 IMU/LED pairs.

Generated test data for a "grasping" motion

TODO: handle practical timestep information:
	different timesteps between inertial and visual data
	more inertial data than visual data (in terms of frequency of
		readings)
	splitting predict and update functions of EKF
Merge branch 'master' of github.com:althomas/phat