Merge remote-tracking branch 'origin/2.0.0'

Conflicts:
	README.md
	dist/metisMenu.css
	dist/metisMenu.js
	dist/metisMenu.min.css
	dist/metisMenu.min.js
	package.json
	src/metisMenu.js
	test/hover.html
	test/index.html
	test/metisFolder.html

update v2.1.2

v1.1.1

update README

rename main files

update readme