Updates to the README and build process

I started with something small and ended up biting off a number of changes here:

- Lots of additions to the README, which references the new setup.sh script as well as improvements to build.sh
- Make the bin-debug folder (for IDE use) and bin-release folder (for shell use and final bit building) easier to use by populating them with a demo file that works and files in video.js
- Build from Apache Flex.  This is the latest version of the SDK.
- Recent changes in Apache Flex allow another change, which is to target an earrlier version of the Flash Player, 10.3.  There's nothing in use that requires the targeting of Flash Player 11- this was forced on all projects with the last version of the Adobe SDK.
- Use a simple HTTP server when testing out Flash.  Given confusing security settings, Flash can sometimes not behave as you expect when running locally.
- Remove old VideoJS.swfs that aren't in use.  They were old, definitely not the latest version, and the new scripts handle this a different way.