Link to instructions or add in readme

[MrEliptik]

First off, thank you for your work.

As an android noob, I had trouble figuring out I was suppose to add maven { url 'https://jitpack.io' } to my buid.gradle file.

Maybe add it in the installation part of the readme, or link to the jipack instructions https://jitpack.io/#uzairiqbal91/CircularTimerView.

Thanks