Fix LaTeX warnings

[WhatisRT]

We don't have to fix all warnings, but it's probably a good idea to go over all of them, try to understand what LaTeX is complaining about and see if there is a simple fix for it. Reducing the number of warnings makes the rest of the output more meaningful.

Here's a rough overview:

• conway-ledger.tex
  • LaTeX Warning: \include should only be used after \begin{document} on input line 10.
  • LaTeX Font Warning: Font shape `U/stmry/m/n' in size <6.57> not available
    (Font) size <7> substituted on input line 2.
• Lots of LaTeX Warning: !h float specifier changed to !ht. Should we just change that to ht in the code?
• Lots of Overfull \hbox
• A bunch of undefined references