Add sage@guug-muc-2013-01-gitify_your_life.tex

Imported from 2012/open_source_days/
Update ikiwiki editing possibilities
Update list of back-ends for ikiwiki
Clarify vcsh slides a bit
First update for git-annex
Use the same names and order for VCS lists
Update URL for bup
Improve Outro
Add slide about git-annex assistant
Fix wrong(!) info about git
Remove old comments
Add cover sheets for each section
Merge branch 'sage@guug-muc' into source