Preparation for sharing

- rustfmt
- clippy
- comments
- README

src/utils/unwrap_or.rs

@@ -1,9 +1,8 @@
-/// A macro version of [Option::unwrap_or_else] which supports
-/// flow control statements such as `return` and `break` in the "else"
-/// branch.
+/// A macro version of [Option::unwrap_or_else] which supports flow
+/// control statements such as `return` and `break` in the "else" branch.
 #[macro_export]
 macro_rules! unwrap_or {
-  ($m:expr; $fail:expr) => {
-    { if let Some(res) = ($m) {res} else {$fail} }
-  }
-}
+  ($m:expr; $fail:expr) => {{
+    if let Some(res) = ($m) { res } else { $fail }
+  }};
+}