Document nightly toolchain requirement

[stefnotch]

I think it'd be worthwhile to document that this crate requires a nightly Rust toolchain for the time being

nodit/src/lib.rs

Lines 377 to 379 in fac00b8

	#![feature(let_chains)]
	#![feature(btree_cursors)]
	#![feature(step_trait)]

[ripytide]

I just checked and we're not actually using btree_cursors or step_trait anymore, it's unfortunate there doesn't seem to be a lint for unused features. Regarding let_chains I use them twice so it may be better so simply refactor those to use normal match statements and allow this library to be used on stable.

[stefnotch]

Oh sweet, I had no idea it'd be this easy to get this library to run on stable Rust.

Would you like to do the refactors, or should I?

[ripytide]

I'll do them/already done them just testing them on stable now.

[ripytide]

released as v0.7.1

[stefnotch]

Thank you very much!