TM4C129X: A small step toward understanding new Tiva clocking
TM4C129X:  First cut at new Tiva clock configuration logic
TM4C129X: Simplify be removing unnecessary temporary variable
TM4C129X: Simplify be removing unnecessary temporary variable
Tiva: Upate GPIO header file for TM4C129X
Tiva: Update UART header file for TM4C129X
DK-TM4C129X: Fix sense of LEDs; active high.  Also GPIO for blue and green reversed
Cosmet updates to comments and README files