Added class template for autosummary.

Copied wholesale from scipy.

I had no end of trouble getting this to work. I expect it only works on
new versions of sphinx (tested on sphix == 1.2.b2)
Updated documentation for solve.py.
Changed l -> m in qho.psi_2d_radial.

m is more commonly used.
Added full wavefunction to coulomb.

`coulomb.psi` is the full (radial and angular) wavefunction for a
hydrogenic atom.
Updated docstrings for Slater determinants.

Now reflect numpy convention.