Added comments and roller and flinger constants

Added comments for the drivebase components
Added flinger solenoid
Added roller solenoids and roller motor ports
modified OI constants

added coments and added joysticks 3 and 4.
added code to enable the compressor

Added constants into robotmap and compressor starting code into
robotInit() in test coast
added roller components to code
added flinger code components
Merge pull request #1 from hazheng/master

Added flinger and roller code