WebLinkback: initial release
WebLinkback: initial release

* Initial release of the trackback/linkback support.
  (closes #627) (closes #857) (references #1136)

tiborsimko/invenio-accounts,inveniosoftware/invenio-accounts,inspirehep/invenio-accounts,inspirehep/invenio-accounts,inveniosoftware/invenio-accounts,tiborsimko/invenio-accounts,inveniosoftware/invenio-accounts,tiborsimko/invenio-accounts,inspirehep/invenio-accounts