Inclusion of git aliases.

Added two shortcuts for cloning from Github and KDE. The "kde:" shortcut
will aways clone from the anonymous server, whereas pushes will be
redirected to the server which requires SSH credentials.

The shortcut for Github repos is "github:". So, for instance, cloning
from https://github.com/roneygomes/dotfiles can be done via "git clone
github:roneygomes/dotfiles".