Remove lecture cruft from notes

- removes references to specific lecture dates
- sets references to use proper BibTeX records.
- removes LaTeX labels automatically entered by org-export.
List contributors in AUTHORS.tex

I've moved a list of the contributors (just me, at this point) into the
separate AUTHORS.tex file and provided a wrapper file to generate it as
a standalone pdf.  This change also required rewriting all of the
copyright notices throughout the source code.
Move 'shared' files into local directories

Maintaining a separate shared preamble and bibtex file seems pretty
unnecessary right now, since things are in so much flux.  So this commit
moves those files into the main 'tex' directory and also dumps the
relevant files from the tufte-latex project into the directory as well
(their repo's a bit bloated with pdfs, etc).
Add bibtex to makefile dependencies
Add RSS URLs to README

GitHub provides RSS feeds that give commit messages for every commit; this
patch adds those URLs to the project README.
Remove chapter/section headings from README

Eventually they'll get out of date, so it's probably better to just
refer interested readers to the main organizational LaTeX files.
Release version 0.2.0

* Removes most of the lecture-notes cruft from the documents;
  references to specific dates, exams, etc.
* Splits the authors list into a separate appendix
* Cleans up the README file
* Moves 'shared' documents into the main repo to make development
  faster and easier.