Added second private key for tests

* In recent v0.10.26 of the crypto library a SignFinal error was raised
  on invalid PEM (SSL) files.
Merge pull request #2 from tomkersten/signfinal_error

Added second private key for tests
userInfo method
alternate client implementation
correction to anvil.callback /token request header and IDToken.verify arguments
corrections to anvil.verify middleware
anvil.verify middleware validates access token claims
Support form-encoded body parameter and URI query parameter with anvil.verify
improved request access token selection logic in anvil.verify
renamed index2.js to index.js