Update installation instructions (to use npm)

pkra · pkra · commit 0ba92ef89749 · 2015-04-01T10:00:10.000+02:00
diff --git a/README.md b/README.md
@@ -14,7 +14,7 @@ of calling the MathJax API.
 
 Use
 
-    npm install https://github.com/mathjax/MathJax-node/tarball/master
+    npm install MathJax-node
 
 to install MathJax-node and its dependencies.
 
