Create SPI library

Started commenting out workflow for spi_setup()
Added example code
SPI setup

Used example data to write spi_setup() with comments. Started
implementing data tx/rx and handlers.
Renamed blink.c to start.c
More stuff
Master SPI test

First try at a SPI MCU to MCU test. For Master
LPM0 Checkpoint

Having trouble getting LPM0 implementation working. Going to switch to
while loops for now.
Working non-interrupt SPI

Communicate from a master MCU to slave MCU. Must connect M_P1.5->S_P1.5,
M_P1.6->S_P1.7, M_P1.7->S_P1.6. Triggers LED on P1.0 when M_P1.3
interrupt trips
Slave in LPM0 SPI
Working LPM SPI

Figured out why LPM SPI wasn't working. Can't go into LPM0 interrupt
waiting inside of an interrupt. Broke spi_tx into interrupt safe active
mode and interrupt unsafe lpm functions.
Changed SPI to return result
updated main to use last change