scroll to change font size

[chtnnh]

add a scroll to change ability to the font size like the timer has the ability to scroll to change the value.

[ishanhemnani]

I have created a pull request adding the scroll feature to the font button #56

kindly review it :)

[chtnnh]

will setup the dev environment on my local and test it out

[chtnnh]

hey @ishanhemnani, i cloned and tested your changes and have left a review on your pr. looks good, except 2 minor changes which i've mentioned. let's get this merged!