remove platform submodule
update paths for flattened repos
modify to use Platform.mixin instead of window.mixin
add 'constructor' to cloned-attribute blacklist, make that blacklist available via exports, whitespace changes
Merge branch 'master' into flattened-repos

Conflicts:
	platform
	polymer.min.js
	polymer.min.js.map
	polymer.native.min.js
	polymer.native.min.js.map
	polymer.sandbox.min.js.map
rebuild
update build
Merge pull request #174 from Polymer/flattened-repos

Flatten repos