TAL-255, modified persona node client to honor scopes, such that tokens are cached with any supplied scope i.e.  token@scope
TAL-255, modified testsuite to connect to http://persona:80/
TAL-255, client now supports caching scoped tokens:
- the node client now caches scoped tokens as token@scope in redis
- modified gruntfile so that tests have a default timeout of 10 seconds
- added unit tests to asser the behaviour of the validateToken method
- added a utils file which contains a getAuthToken utility for the tests
- utils file also contains methods for returning stubRequest and
  stubResponse objects, this is because we use the node client as
  express middleware, that accepts req and res, these need to be honored
  but also provide a way to assert whats happened
TAL-255, bumped up version number
TAL-255, tidied up code based on feedback. create a cacheKey up front which we use for the lookup, and does not overwrite the original token
Merge pull request #1 from talis/TAL_255_token_scope_verification

Tal 255 token scope verification