WebStyle: legacy template integrated in Invenio

* The legacy page rendering as well as JavaScript block has been
  integrated in Invenio, and thus removed from ZENODO repository.
OpenAIRE: migration of OpenAIRE users

* Removes old users from the Orphan Repository.
WebStyle: fix type in page template.
WebSearch: rename usage tab and remove graph

* Rename Usage statistics to Related content

* Remove download graph.
installation: add WinPDB to requirements

* Ensure remote debugging can be done in virtualenv as well.
OpenAIRE: fix unicode decoding error in form

* Non ASCII characters in names would throw an exception.
WebSearch: fix block in custom template

* Block overwrite was outside an if, causing errors with of=id in search
  parameters.
WebStyle: open menu on hover instead of click

* Open main menu on hover instead of a click which is the default
  bootstap behaviour.
OpenAIRE: fix missing template variable.
OpenAIRE: fix collection definition to use 980__a
OpenAIRE: integrate new submissions more quickly

* Ensures new records are integrated much quicker into Zenodo (closes #1355).
BibFormat: link collection and access right labels

* Links collection and access right labels from brief and detailed
  HTML formats (closes #1392).