simplified logic, fixed tests
added copy method
added len method
working slicing
added repr_X property
added plot method and test
remove old particle, leave commented out observe stuff
minor typos
remove dynamical base bullshit, fix imports
made Orbit a particle subclass w/ time
stupid, gotta check shape of t
time axis is -1 now (last one)
updated tests
fix particle test to use nparticles
test for plotting, now gotta write the method..
added plotting for orbits
check for dimensionless units
do 6d case