Update resources to subclass Serrano's ThrottledResource base class

Fix #133
Allow Serrano to handle authentication of the API resources
Update NamedSampleResource to bypass Serrano's authentication check

This resource must be publicly accessible, so the Serrano-based
authentication must be ignored.
Flake 8 fixes
Merge pull request #134 from cbmi/issue-133

Update API resources to use Serrano's base resource class