Restructure wrappers a bit to simplify the code

This also fixes #65

Now all wrappers are hanging of scope.wrappers.
Merge pull request #73 from arv/restructure-wrappers

Restructure wrappers a bit to simplify the code
add gruntfile.js for building shadowdom.min.js, factor main portion of test runner into test.main.js, create test.min.html to run tests against minified source
Merge pull request #75 from sjmiles/master

add grunt task for minifying code, factored test code so we can run against full source (index.html) or minified source (index.min.html)