updated tools/release.js to use uglify-js 2.x

Added some slight updates to the tools/release.js. 

Updated the uglify(src,dst) function to use uglify-js 2.x's simpler api, using the minify function for parsing, compressing, and generating output code.  There might be some reason why uglify-js 1.x is being used, but because the last update was 2 years ago, I just assumed it needed some love.

Also changed the file read of package.json to be looked for in the root, to be consistent with the rest of the file reads, as well as to build the bundled files on a Windows machine where one might not have access to make, figuring they are running node release.js from the tools directory (It also requires the creation of a dist directory, but that can be done manually.)