Adds gitignore.io to the tips page #324.
Adds gitignore.io to the tips page #324.

dotfiles/dotfiles.github.com,unixorn/dotfiles.github.com,dotfiles/dotfiles.github.com,unixorn/dotfiles.github.com,unixorn/dotfiles.github.com,dotfiles/dotfiles.github.com,unixorn/dotfiles.github.com,dotfiles/dotfiles.github.com,dotfiles/dotfiles.github.com,unixorn/dotfiles.github.com