- cleaned up interface
- made read functions return phyical values
- made resolution configurable at initialization time
- added default parameter configuration file
- added SAUL support for the driver
In general, data transferred through I2C are bytes and thus should have
type uint8_t, not char.
Also convert uint8_t ptrs to void ptrs
Change i2c_write_bytes to i2c_write_byte because it was
seriously wrong at this point.
fix doxygen warnings
change default address