add README.md

README.md

@@ -0,0 +1,19 @@
+## Rust Util
+
+
+Config `Cargo.toml`:
+```
+[dependencies]
+rust_util = { git = "https://github.com/jht5945/rust_util" }
+```
+
+Use in `*.rs`:
+```
+extern crate rust_util;
+
+...
+
+use rust_util::*;
+```
+
+