add series interface

this is a quick interface I threw together to show the list of current series as well as their column names (at least the columns for the most recent record).

this addresses issues #17

![screenshot 2014-04-27 16 09 02](https://cloud.githubusercontent.com/assets/1320353/2812222/086552e4-ce48-11e3-9916-1f992dacdcc2.png)