[MetroMPG]

I'm still planning to incorporate the temperature feature as well. Also possibly a line showing the "hypermiler" threshold (20% over EPA combined) - but that depends on how busy the graph gets. Don't want to overdo it.

I will be switching gears when those items are finished and working on some other tasks, then returning to the log to set up the "Long term" & "short term" versions for people like brucepick who have tons of data and whose long term graphs are too packed for labels & pretty spacing.