ADD NEXT and PREV Link for seamless reading.

[TripleteSumit]

Hey Genzyy,

I read your notes. They're really fantastic. While I read the notes, I feel uncomfortable every time I go back to the index page and select the next section. So, I think it's better to add a link to the next page and the previous page. It creates a seamless reading environment for every reader.

[TripleteSumit]

assign the above work to me.