Moved init routines to common.c/h; Accel values corrected

Moved the setup function and separated it into more manageable methods,
they are now in the common.c/h files.

Accelerometer values are handled better in the check_accel() method; ignore
alert bit and determine positive/negative. The values seem quite off, but
I'm sampling at a low rate and I'm not averaging any values. Next up
for the accelerometer is tap and shake detectection. This will require the
setup of port B2 interrupt capabilities, which is partially implemented in
this commit.
Shake Detection working with polling

Getting good shake detection from the accelerometer. However, the pic
interrupt handler and configuration doesnt seem to be working for the
INT2 (PORT B2) external interrupt. The test of the shake detection is
done by polling the INT2 interrupt flag. Therefore, the interrupt is
actually being thrown on the pin and the flag is being set correctly,
but it is not launching into the interrupt vector. Needs more investigation.