GitHub not Github in plain text emails.
Update CLA Signature mailer language.

A user signs the ICLA not an ICLA. A new CLA is not created when someone or some
company signs the agreement, a new signature is created. This is more consistent
with the rest of the app.
Update the Dashboard cookbook share content.

When a user does not own any cookbooks, display the commands for sharing a
cookbooks and add a link to the full docs. This commit removed the info about
the Supermarket Knife plugin since users should be able to just use
regular-ole-knife (ROK) since it follows redirects.
Merge pull request #562 from opscode/mailer_copy

Mailer copy updates
Merge pull request #563 from opscode/dashboard_share_update

Update the Dashboard cookbook share content.
track hits in segment.io
adding a hit counter for /universe
switch to label/total instead of universe