changed reference code from durva for display

Signed-off-by: Shivdas Gujare <shivdas.gujare@gmail.com>
display temperature
printing temperature in deg celcius on display
Print Light sensor reading on display at row 2

Signed-off-by: Shivdas Gujare <shivdas.gujare@gmail.com>
implemented way to enter to setting mode
changed snesor reading functions