Ignore patch level for ruby version.
Check for updated version of comet.

Pings the rubygems API to see if the latest version of comet is
greater than the current one.

Also moved around some code to better support integration testing.
Add library for comparing versions.
Only check for newer versions on certain commands.
Add more tests for checking for updates.

Verify that the user isn't presented with an update notice if they
have the latest version of the gem.
Move setup code to module.
Define custom example group for CLI tests.

Stubs out any network calls and provides a temp working
directory with comet configuration.
Display useful notice when unauthorized.
Version bump.