v0.6: Asteroid exploration and reconstruction

Now we can do the following:

* C++ polyhedron potential model
* Determine best (lowest cost) states to update the shape of an asteroid
* Use this shape estimate to compute the full SE(3) control
* Dynamically simulate the motion of a rigid body around an asteroid
* Autonomously update the shape using LIDAR measurements

To explore an asteroid using the full dynamic simulation (somewhat long time):

~~~
ipython
run exploration_sim.py -c <name of hdf5>
~~~
Plot the output using

~~~
run exploration_sim.py -r <name of hdf5>
~~~

If you just want the kinematics (fast):

~~~
./bin/explore_control -o <name of hdf5>
~~~

You can then plot

~~~
run dissertation/explore_plots.py <name of hdf5>
~~~