Improve README slightly

Author: NoraCodes

README.md

@@ -1,8 +1,12 @@
+# libUI
+A Rusty user interface library that binds to platform native APIs. 
 These are work-in-progress Rust bindings to the minimalistic native UI library [libui][libui].
 
-They require GNU Make and CMake to build `libui` itself.
+## Building
+`libui` is included as a submodule. You will need CMake to build `libui` itself; 
+after that, Cargo should be able to take care of the build process.
 
-Author: Patrick Walton (@pcwalton)
+Based on work by @pcwalton
 
 [libui]: https://github.com/andlabs/libui