Added a test for avgflyvelocity
In fly we made x and y  position and x and y  velocity arrays with a length equal to the number of frames. We also made getters and setters for these.
Added some tests for averageVelFly, and made the method that averages the velocity of a fly over a given range of frames.
Merge branch 'AverageFlyVelocity'

Conflicts:
	src/edu/lclark/drosophila/ButtonPanel.java