don't count DoubleExponentialDisk and RazorThinExponentialDisk coverage on travis, because we cannot use them (they are tested manually)
bunch of tests of the Orbit interface of actionAngleSpherical
test Orbit interface to other actionAngle methods
don't support xw
test toLinear and toPlanar
test angular momentum
test more cases of adding orbits and of pickling
start on testing orbit plotting, fix plotE for planarROrbits
fix plotvz
much more testing of orbit plotting
rm _callRect (does not seem to be used)
different, better, way to intialize the various OrbitTop subclasses
store vxvv in OrbitTop to fix the new initialization of OrbitTop subclasses
remove some of the util code from coverage, as multi isn't galpy code and testing bovy_plot is quite meaningless
start on testing bovy_coords
test lbd_to_XYZ and inverse