Fixed GoDoc badge.

Fixes #119

Reduce variable name restriction

Updated README w/ runnable example. Addresses #32.

Fixes #66

The router now associates a regexp named group with each mux variable.
It only fills variables when capturing group name match instead of
relying on indices, which doesn't work if a variable regexp has interior
capturing groups.

Fixes #62

Add note about the availability of CurrentRoute.

This is a copy of commit d6bce32a36 from
Go core.

Issue #16: Added regex support for matching headers

Fix a typo

Issue #109

Update the walk method  …

fix for empty query

- GetOrgMembership updated to accept user parameter (BREAKING CHANGE)
- EditOrgMembership updated to accept user parameter (BREAKING CHANGE)
- Added new RemoveOrgMembership method

Ref #187

- Add new options struct to AddCollaborator (BREAKING CHANGE)
- Add Permissions field to User struct, which gets populated when
  calling ListCollaborators

AddTeamRepo's "permission" option and AddTeamMembership's "role" option
should both be passed as part of a JSON request body, not as URL query
parameters.

- AddTeamMembership and ListTeamMembers both take new Option structs to
  specify role.  (BREAKING CHANGE).
- Add Role to ListMembersOptions
- update Permission and Role docs

Ref #187

update CreateTeam and EditTeam to pass preview media type if
Team.Privacy is set.

Ref #187

- allow setting permission when adding a team repository
- update IsTeamRepo to return a *Repository instead of a bool, since the
  Repository contains the permission data for the team.  This is a
  BREAKING CHANGE, however I don't think this is an often used method.
- update docs for setting the team permission when creating or editing a
  team.

Ref #187

These changes are now official, so the custom media type is no longer
needed.  This does go ahead and remove RepositoryListOptions.IncludeOrg
which was being used to trigger the custom media type.  Even though this
is a breaking change, it was only in for a month and I don't think it
was too widely used during that time.

Fixes #219
/cc @captncraig who may have been using this

Change-Id: Ib54ced78c51a9c4e54e470136d36f91bf4716e8c

Conflicts:
	mux.go

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