Add unit tests around session timeout and local storage expiration
Verify that a change to the session timeout affects the local storage expiration
Spec to verify that the Auth API contract is followed by the SecurityContext; Convert "console.log" statements to "$log.debug" in the SecurityContext
Add spec to verify login and logout management of the user data in the SecurityContext
Add documentation to the README.md that the Auth implementation must be provided by the parent application and no particular implementation is assumed
Update based on questions in pull request feedback; Allow the Auth module and implementation names to be provided by the application that uses the security context module
Fix issue with running `gulp test`
Merge pull request #1 from crdschurch/docs-and-tests

SecurityContext unit tests