Update readme

README.md

@@ -2,3 +2,26 @@ natronics.org
 =============
 
 just a webpage
+
+<https://natronics.org>
+
+
+### Install
+
+Built with [Cobalt.rs](https://cobalt-org.github.io).
+
+```
+$ cargo install cobalt-bin
+```
+
+Needs some js to support LaTeX equations
+
+```
+$ npm install
+```
+
+### Build
+
+```
+$ make _site
+```