Update required in README instructions

[ashryaagr]

In the README, modifying-literate-scripts section says "add/modify tutorials in the scripts/ folder". But it should be _literate/ . No scripts/ folder exists.

In the README, visualise-modifications-locally section uses JuDoc to serve. But on using JuDoc.serve(), I get a message JuDoc.jl is being renamed to Franklin.jl. JuDoc.serve() gives "directory missing" errors which can be seen below.

But Franklin.serve() works perfectly.
So I suggest that JuDoc.serve() be replaced with Franklin.serve()

[tlienart]

Yes! kindly open a PR with these changes, thanks!