Update fonts to use PUP fonts or other family with good math symbols/spacing

[Richard Murray]

The current fonts that are being used for the draft version (mathptmx = Times Roman fonts w/ math fixes) generates a lot of ugly symbols and bad kerning for some subscripts. We need to identify a final font choice that looks better.

Things to check

• \mathcal fonts (e.g., {\mathcal N}, {\mathcal C}, {\mathcal P})
• summation side
• subscripts (e.g., {\omega_\text{b}})
• \widebar (doesn't exist in mathptmx)

[Richard Murray]

The new version of the PUP style files using Computer Modern fonts instead of Times Roman and this fixes up the math problems that we were seeing.