Load AudioManager and SoundManager2. Default to SoundManager2 unless
users of the JavaScript SDK pass { enableRTMP: true } to the SC.stream
method.
Copy soundmanager swf files to build dir
Backing out changes that break backwards compatibility.

Will need to work versioning into the build process before re-introducing
these changes as they require a major version bump.
Specify uglify-js version. Newer version is 404'ing
Pin sm2 to specific commit