Makefile: default to 'make all', other fixups

* Don't invoke 'make' and 'mkdir -p' multiple times.

* Create a proper "order only" dependency for the OUT directory.

* Build the PDF and DVI version automatically when you type 'make'.
  (This was broken and would cause errors if you just typed 'make',
  since it would try to build the DVI version without performing the
  text/bib/tex/tex build necessary to get the references right.)

* Setup dependency for any bibtex files and for the template class file
  itself, so we re-build whenever the template is modified.
.gitignore: ignore Vim swap files