Add camera functions in scribe.py file

[nk521]

Read https://picamera.readthedocs.io/en/release-1.13/recipes1.html for a start. Implement functions for these so that they can be called afterwards.

For example:

...
def cam_brightness(x):
    if x in range(0,101):
        camera.brightness = x
    else:
        return "Error : Brightness level is out of range (0-100)"
...

Before adding any setting function just make an issue for the same and then open a PR.
Happy Coding :D