New Janitor wiki page

Hi all,

There is a new "Janitor" page on the wiki:

http://git.or.cz/gitwiki/Janitor

Right now, there are no links to it from other pages, but feel free to add 
one or to tell me to do so.

The only item on the page is about converting code to 
use "git_config_string". Feel free to add more items.

Thanks,
Christian.