Add my own blog and the GTRR to the list of example sites

[artemislena]

I've been using Cobalt successfully and have a few templates and such for those two (especially the latter might be interesting; it has a Liquid loop for getting a path like /you/are/here with links to the appropriate parent paths), so I thought it could help for extending your documentation as well as helping Cobalt advertising itself (and me advertising my sites) with a longer list of sites…