GUI-1209: Create bucket/folder

Implements the following for https://eucalyptus.atlassian.net/browse/GUI-1209 …

* Create Bucket (linked to from button on buckets landing page and on the dashboard)
* Create Folder (modal dialog opened via button on bucket contents page)
Completely agree we should refactor the validation code for reuse.  Angular 1.3 has some nifty features w.r.t. form validation we may want to consider leveraging in an upcoming console release.  See http://www.yearofmoo.com/2014/09/taming-forms-in-angularjs-1-3.html