Update readme, conda install, wrong channel

[Wholinator]

Upon copy pasting this into my terminal, I received a package could not be found error. I searched anaconda and found an extremely similarly named channel, with just 2 characters transposed. https://anaconda.org/rmg/py3dmol

Sincere apologies if I've done this wrong, this is my first contribution here.

[alexvakimov]

Thank you, for the fix @Wholinator . Looks right.