- Added .gitignore.
- Adapted release.sh script to git.
- Removed :version from cffi.asd. Release tarballs now get the release
  version inserted into the tarball's cffi.asd.
- Update manual with git info.

Bug fixes / tweaks:
- fixed typo in foreign-enum-value.
- defcenum: renamed argument, allow a docstring.
- defcvar and defcfun: also accept symbols as names.
- defcvar: added (declare (ignore value)) when read-only is true.
- foreign-funcall: fixed bug; premature canonicalization of the
  return-type. added regression test for this.
- defcfun and defcallback: use the make-gensym-list utility
- defcallback: return the callback name;
- strings.lisp: fixed the docstrings for the :string translators;
- mem-aref: fixed bug/typo in its setf-expander; added regression
  test for this.
- defcstruct and defcunion: allow a docstring.
- new tests: callbacks.qsort and funcall.string.3

Documentation:
- New file doc/Makefile for generating docs and uploading them to
  c-l.net.
- Added every cffi function/macro that is currently exported.
  documented half of them or so.
- colorize-lisp-examples.lisp: little script to colorize the examples
  in the texinfo-generated html docs.
- gendocs.sh: generate the docs in various formats as well as an
  index page from gendocs_template.
- further tweaks to doc/style.css.

- Commented out some unused forms in src/functions.lisp.
- Defined our own SQRTF in libtest.c since it's not available
  on win32.