Fixed setting css on button for closed folder.
Merge branch 'master' into gh-pages

Conflicts:
	test/test.js
	tree.jquery.js
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Added option 'selectable'.
Added tutorial.
getSelectedNode: return false instead or null. Necessary for jQueryUIm5.
Merge branch 'master' into gh-pages

Conflicts:
	extra/css/documentation.css
	index.html
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages
Merge branch 'master' into gh-pages