Issue #16: Added regex support for matching headers

Issue #16 : Addressed code review and refactored support for regex into
a separate function

Added compiled regex to route matcher

Ensure flags are parsed before calling bind.Default().

Tested by running `./example -bind localhost:1234`.

I suspect this is worth some perf, but it's probably not enough for us
to care. More importantly, it breaks in Go 1.5, where a recent
optimization made sync.WaitGroup much smaller.

Add goji.ServeTLS and goji.ServeListener functions.

There's already a ListenAndServeTLS function, but Serve conveniently
handles calling various graceful and bind methods.

GitHub occasionally changes the IP addresses from which GitHub Pages
websites are served. For users of the service, they must upgrade any A
records to these IP addresses to continue using the service. This patch
provides this data in the `APIMeta` struct as the property `Pages` and
populates from the /meta endpoint.

Release Announcement:
https://developer.github.com/changes/2015-06-11-pages-a-records/

Fixes #212.

Fix example greet

ocd kicking in :)

Fixes #120.

This helps avoid a gotcha when using matches with sub-routers.

Fixes #120.

I think this is a regression introduced by c1922ab1.

Fixes #130.

Fix typo

Supports the updated starring API as mentioned in issue #188.

There is now a new struct called StarredRepository which holds a Repository and the new `starred_at` timestamp.
For now there is a special media type to request the new API. I've added a TODO for it to be deleted when the new API fully launches.

There's no way of serializing/requesting an empty required_contexts that
is needed for bypassing the commit status checks for the ref.

It's a breaking change but will allow to serialize an empty array and
omit empty value as expected.

Add complementary test for patterns with pipe

Fixes #185.

Memberships API is now official.

https://developer.github.com/changes/2014-09-16-finalizing-the-organization-and-team-membership-apis/

Fixes #192

Deployments API is now official.

https://developer.github.com/changes/2014-11-25-the-deployments-api-is-official/

Fixes #189.

Both have been deprecated.

Fixes #190.

- AddTeamMember: https://developer.github.com/v3/orgs/teams/#add-team-member
- RemoveTeamMember: https://developer.github.com/v3/orgs/teams/#remove-team-member

Also:
 - add PingHook to RepositoriesService
 - move ListServiceHooks to Client, since hooks are no longer just for
   repos.  Leave behind Repositories.ListServiceHooks for backwards
   compatibility

Fixes #178

The client_id and client_secret URL variables,
containing sensitive app information, are leaked
to users if the Go error is returned to them. To
prevent this, sanitizeURL redacts the fields from
ErrorResponse's Error method. Therefore making the
error message safe to expose to users.

(not added to AUTHORS - Google owns copyright)