Update to select2 3.4.5

Source from https://github.com/ivaynberg/select2/releases/tag/3.4.5

Minified JS for locale files were generated with
`uglifyjs -m -c --comments all`.
Minified CSS for select2.css was generated with uglifycss.
Merge pull request #2297 from flatironhealth/master

Update to select2 3.4.5