Instructions for how to install Sublime Text 2 completions file.

I bet there is a "righter" way. But that's how it's working for me.

utils/editors/sublimetext2/README

-zip threejs.sublime-package threejs.sublime-completions

utils/editors/sublimetext2/README.md

+### How to install
+
+1. Compress `threejs.sublime-completions` into `threejs.sublime-package`.
+
+```shell
+zip threejs.sublime-package threejs.sublime-completions
+```
+
+2. Copy the compressed file into `Sublime Text 2/Pristine Packages`.