Pass a User-Agent when fetching data from the GitHub API

See <http://developer.github.com/v3/#user-agent-required>.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Check GitHub API rate limit instead of silently failing

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Added support for a GitHub Personal API Access token

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Remove unnecessary rescue-all exception handling

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Hoist requires out of methods