Update gh-pages: benchmark, docs, code coverage report

Changes:
 * benchmarks fixed to run on chrome
 * update to latest handlebar and mustache
 * mustache bench working again
 * using latest Dust 2.2.3 in comparisons

 * coverage page now uses the latest test results running with istanbul (still need to do this manually unfortunately). Test are on the full minified file which more closely represents the browser environment but has less data (minified = 2 lines of code)

 * dist directory cleaned up to mirror whats in master. updated with the recent version from master `git checkout master dist/dust-full.min.js`
 * pointing benchmark, test/test.html to this dist directory

* update documentation to reflect `grunt` instead of `make`

* remove `vendor` folder which isn't used here. t'was copied from master.