Fix LaTeX to support and remove Notes/None

[nspark]

This PR:

• Fixes the LaTeX environment to allow removing \apinotes{}
• Removes all instances of \apinotes{ None. }

Replaces #87

[nspark]

Ugh. Here's one of those "it works on my machine" problems.

[nspark]

Renders of the PDF as of e12a415:

[nspark]

@manjugv @jdinan This PR is ready for review; I'd like to have an informal review at the F2F