Add gravatar template. Add template to devs and groups.
gravatar-url -> gravatar-id and extract id from gravatar URL.
move header/footer links to _config.yml
Merge pull request #28 from kylegordy/master

move header/footer links to _config.yml
add IRC to resources
remove IRC from header/footer
Merge pull request #29 from kylegordy/master

remove IRC from header/footer, add IRC to resources
Merge pull request #26 from seabre/only-use-gravatar-id

Use gravatar id for devs and groups instead of URL.