Refactored common strings in lcd printState.

before
    Program Memory Usage  : 28732 bytes   87,7 % Full
    Data Memory Usage   : 698 bytes   27,3 % Full
after
    Program Memory Usage  : 28682 bytes   87,5 % Full
    Data Memory Usage   : 738 bytes   28,8 % Full
refactored compare and substract into updateWaitTime. Saves 48 bytes.
before (revA, leonardo)
    Program Memory Usage  : 28682 bytes   87,5 % Full
    Data Memory Usage   : 738 bytes   28,8 % Full
after
    Program Memory Usage  : 28634 bytes   87,4 % Full
    Data Memory Usage   : 738 bytes   28,8 % Full
removed internal methods from public Display interface
printDegreeUnit takes location - saves 30 bytes
use printAt - saves 62 bytes
Display::printAt -> Display::printAt_P