Modified igor's delayMicroseconds fix; more accurate & consistent delays
CC3200 wiring.c reworked - new delayMicroseconds(), modified delay(), fixed micros()
Backported SysTick-only implementation from cc3200 to Tiva, removed Timer5 IRQ stuff, ported strawman sleep/sleepSeconds/suspend to CC3200.
Reinstated attribute((weak)) in startup_gcc (had an outdated copy of startup_gcc.c in my install)
removed reference to Timer5IntHandler since it's not used on cc3200 at all
Fixed cc3200 startup_gcc.c, had clobbered Robert's syscall functions.
Merge pull request #475 from energia/issue_475

ARM SysTick-based delays need fixing