Currently, the AUR sites are hard to distinguish from the official
website, especially when browsing Git repositories in cgit. Add "user
repository" to the logo to make it distinguishable from the official
site.

In order to avoid confusion, also change the link in the logo to the AUR
home page instead of the main Arch Linux website.

Signed-off-by: Lukas Fleischer <archlinux@cryptocrack.de>