Add cargo-install instructions to install.md

[egranata]

I was not aware of cargo-binstall and assumed it to be a typo. cargo install seems to work, and cargo binstall requires an extra step, worth documenting IMHO

[mistydemeo]

cargo install installs from source and from non-locked dependencies (which has broken before!), so I think I'd prefer it if cargo-binstall came first. Make sense to you?

[egranata]

cargo install installs from source and from non-locked dependencies (which has broken before!), so I think I'd prefer it if cargo-binstall came first. Make sense to you?

Yeah makes sense. I have updated the PR with swapping the two. Of course, I can't seem to squash the two commits into one, so that's something you may wanna do when you merge this?

[mistydemeo]

Actually, I just noticed the section right below this is for cargo install. I get that with binstall coming first there was some confusion around what this was meant to be - maybe we can reword the header for the cargo install section that's already there so it's clearer what it's suggesting?