Updating to jwcrypto@0.4.2

* Make publicKey retrieval async
* Removes last vestigates of cert chaining
* Couple style cleanups
Adding travis config
Merge branch 'issue-118-upgrade-jwcrypto' into train-2013.01.17
Adding custom logger and using stream with express logger. Fixes #121
Merge pull request #122 from mozilla/issue-121-logging

Issue 121 logging