Rancid-git default support

I was upgrading to a new rancid version with default git support and noticed that Observium had git support, but did not support the 'default' config from rancid for git itself.

In our case we use 'LIST_OF_GROUPS=""' in the config, so configs are located in different folders, and you have a .git in every folder.

Note: this will break the other implementation, but that wasnt stock rancid either