[merge request] Some docs.

[Teika Kazura <teika lavabit com>]

Hi, please merge my branch. It's doc:

* Polished news.
* Corrected edge-flip docs.
* Supplemented lacking description of subrs: (un)grab-keymap,
  x-raise-window, x-lower-window, and frame-state-mutex.
* In sawfish.texi, all "#!optional" are put into @t{..}.
* comments.

Chris, if you like a fix in edge-flip / infinite-desktop after
screen resolution change, look at src/flipping.c. It must be
easy.

If you can't fetch from the gitorious repo, please use temporarily
git://gitorious.org/sawfish/sawfish.git

Teika (Teika kazura)