Update .gitignore file

Add the lines below

ltxpng/
/org/drafts/*.html
/org/drafts/*.pdf
/org/drafts/*.tex
Add draft post about using the 'beets' program

[Beets](http://beets.radbox.org/) is a nice way to keep your music
library organized. It uses [MusicBrainz](musicbrainz.org) to get the
metadata.
Add draft post (in org-mode) about point processes