Fix javascript on /record/managedocfiles

* Downloads properly jquery.form.js from bower.io
* Reorders the `<head>` so the bundles are present when some legacy script tries to inject what it has to[1]
* Adds a dummy script to preload UMD/AMD-ready modules to be used outside a require.js context (dirty hack, but it works)

**NB:** the uploads triggers a 500 error:
```
...
File ".../invenio/legacy/bibdocfile/managedocfiles.py" line 1819, in wash_form_parameters
  form_file = form_field.file
AttributeError: '_io.BytesIO' object has no attribute 'file'
```

ping @pbroz -- fixes #1900

[1]  in the most dirtiest way possible (of course).