easy build on Mac OS X (shell script + AppleScript Chrome automation)

This basic build process may eventually be streamlined with the existing Rake configs for each individual "submodule", but in the meantime this is a pretty useful way to update all templated JS files in the development/ and /lib folders.

The Mac-specific Chrome automation part should be separated in the future. Right now it closes the browser and re-opens in incognito mode with extra command line flags to prevent caching and to allow local file access (without having to run a server).