* version number is stored in version.yaml
- work in progress is marked with version number that ends with '-snapshot'
* all compiled files are stored in the './build/' directory without version numbers
* :package task creates a tarball in the build directory
- if version number contains '-snapshot', this substring is replaced with sha of the head
- tarball contains version number in the filename
- all js files contain version number in the filename
* .gitignore was updated to reflect all these changes
* the .map file is not created by the closure compiler any more
* embedded images as data URIs
* rake task to generate multipart js file with embeded images for IE
* move images into a separate directory outside of src or css and
keep them there for reference
* clean up Rakefile and ruby code
* .gitignore update
* don't penalize IE 8+ with an extra request to the ie-compat.js file
