Documentation sprint: Terminfo documentation strings

[olleolleolle]

Rust doc sprint: adding doc strings to the Terminfo library.

This is my very first Rust repository PR, so please do not hold back any formatting, nit-picky commentary. I need it.

[alexcrichton]

Why is this hidden? I thought this was one of the main exports of this library?

[olleolleolle]

I did not know how to do explain the "all the fields of this are priv", yet the main thing is not, so a very short docstring, like Wraps an output stream and its terminal settings may do the trick.

Thanks for picking this piece of lint.

[alexcrichton]

This structure is one of the main exports of this library, just because its fields are private doesn't mean that it's a useless structure. The HashMap structure, for example, has no public fields.

Documentation on structs normally explains what it's used for and why, accompanied with an example or two of its usage.

[alexcrichton]

A good check would be to put #[deny(missing_doc)]; in lib.rs, and the compiler will check to make sure that everything is documented.

[brson]

@alexcrichton is this ready to go yet?

[alexcrichton]

Not quite, I still have some comments that I would like addressed

[olleolleolle]

1. "Things have been crazy here", so I haven't had given this the Rust-love it deserves
2. I agree with all of Alex's kind and helpful comments.

[olleolleolle]

And, now it also built green. @alexcrichton@brson Would this suffice?

[flaper87]

A new snapshot was created today, this line could go away already.

[flaper87]

@olleolleolle would you mind squashing the commits?

[olleolleolle]

@flaper87 Thanks for picking that up. 🍰

[olleolleolle]

(Darned thing stopped, "no output for 10 minutes" error.)

[olleolleolle]

Thanks, @kud1ing for noting Markdown deficiency.