Adding travis build file.
Merge pull request #11 from proppy/master

remove cache
Merge branch 'master' of github.com:rakyll/oauth2
Add build status.
oauth2: don't use http.DefaultTransport.

http.DefaultTransport is not available on App Engine.
App Engine Managed VMs should depend on url fetcher.
Revert "App Engine Managed VMs should depend on url fetcher."

This reverts commit 4901e89da79a1d4f2d0d53e762de98c66428f21d.
Use default client rather than a new client instance.
Export Transport to allow default transport to be configurable.
Fail during conf init if auth or token URL is not valid.
Remove named return values.
Clone authURL.
Make AccessType, ApprovalPrompt and RedirectURL optional.
Merge pull request #15 from stacktic/dropbox

Making AccessType, ApprovalPrompt and RedirectURL optional
Avoid concatenating scope literals.
Export exchange.

Allows users to exchange and retrieve a token
without initialising a Transport.
oauth2: Allow use of arbitrary RSA private keys to sign JWT token retrieving requests.
Docs, code cleanups.
Fixing json tags.
Docs improvements, lint error fixes.