Small cleanup of headers, compile errors.
Merge pull request #34 from ptressel/master

Small cleanup of headers, compile errors.
Using unique name for C3 LED
Power and ground traces
Routed
Proto area; thickened traces
Rear facing sonars; angles adjusted
Silkscreens; smaller sonar board
Silkscreens; smaller sonar board
Merge pull request #35 from TylerFolsom/master

BOM for fabricated PCBs
Merge branch 'master' of github.com:elcano/elcano