Makefile, Makefile-shared added.

This Makefile allows to created a shared library
libimu.so that will be used by imu.py through
ctypes.
accelcal.txt, magcal.txt: calibration files added.

These files are overwritten by imucal.
Makefile added.
imu.py: sensor initialization provided.

A first attemp to reuse the read functions from
the C code has been done however it seems there's
some sort of trouble with it. C functions will be
coded that return the information as a parameter
passed by reference.
imu/imu.c: getting started with C
functions to read the information
from the sensor.