Data logging and Graph Support

Added a status logger that logs every status change.  This also reports on series of data (temperature and duty changes).  There is a new API call /graph that will display an html graph and updates in real time.  There is also a call /graph-data/ that displays the data that powers this graph.  Files from each run will be written to /graph-data/<timestamp>/..

Eventually the graph will need to be better integrated into the UI.

Also plan on adding support for displaying previous runs.