gitx install instructions

Author: mxcl

README.markdown

@@ -6,6 +6,14 @@ Vertical split, minimized UI, curated layout.
 
 ![Screenshot](Documentation/Screenshot.png)
 
+## Installing the Terminal tool
+
+We bundle this for our classes as part of another installer. The other installer installs `gitx` for our students`.
+
+You can install it by hand:
+
+    cp /Applications/GitX.app/Contents/Resources/gitx /usr/local/bin
+
 ## How to Build & Install:
 
 See [the wiki page](https://github.com/gitx/gitx/wiki/Build-instructions)