deposit: static file fixes
deposit: static file fixes

* Added missing plupload to Bower and Grunt;
* Fixed wrong location of jQuery UI themes.

Signed-off-by: Adrian-Tudor Panescu <adrian.tudor.panescu@cern.ch>

NOTE: beware, patch amended by Tibor to use new file names

inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit,inveniosoftware/invenio-deposit