[Build] Power use in wiki

[Ben Kochie]

I've started adding some of the heavy power items to the wiki.

https://www.noisebridge.net/wiki/Electricity

It looks like we're behind on updating the wiki with power bills.  Someone 
with access to PG&E website should update it.  It would be nice to add 
full bill files and separate KWh use per panel based from the online 
account history.

-ben

  "UNIX is user-friendly, it's just picky about its friends."