Fix node@0.8 in Travis CI

Adding fix for node@0.8 in Travis CI
Release 0.2.1
Moved off of `keys` to support `twemproxy`. Fixes #7

Merge branch 'master' into bug/stop.using.keys

Added notes about twemproxy support to README

Fixed up bad `this` reference

Completed hash tracking

Fixed up bad this.id reference

Added collection equivalent of models

Filled out new method for deleting model info

Updating cache reference methods

Updating comment to meet new intent

Removing reliance on redis-delete-pattern