lib: improve docs and lints (#15)

This adds some sanity lints and fixes a few typos in docs.

src/fs.rs

@@ -20,7 +20,8 @@ struct RmdirContext<'a> {
     counter: u64,
 }
 
-/// Reliably removes directory and all of it's children.
+/// Reliably removes a directory and all of its children.
+///
 /// ```rust
 /// extern crate remove_dir_all;
 ///

src/lib.rs

@@ -1,3 +1,11 @@
+//! Reliably remove a directory and all of its children.
+//!
+//! This library provides a reliable implementation of `remove_dir_all` for Windows.
+//! For Unix systems, it re-exports `std::fs::remove_dir_all`.
+
+#![deny(missing_debug_implementations)]
+#![deny(missing_docs)]
+
 #[cfg(windows)]
 extern crate winapi;