errorlib: fix Sentry context syntax issue

* Fixes Python syntax issue that slipped in the Sentry context support
  commit d73bd94b2fbe8666af31dfec25c334c466e6f6df.
  (addresses #1960) (PR #2147)

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
BibCirculation: fix for CERN returnees

Acked-by: Tibor Simko <tibor.simko@cern.ch>
WebSubmit: Autocompeltion for authors

* Provides an author autocompletion facility for WebSubmit. (closes #2276)

* The author autocompletion interface can easily be configured for each
  submission.

* Author sources can be defined as plugins that return results in JSON.

* Author submission and modification are fully compatible with existing
  BibConvert templates.

* Uses typeahead.js <http://twitter.github.io/typeahead.js/>
  for autocompletion.

Co-authored-by: Harris Tzovanakis <charalampos.tzovanakis@cern.ch>
Co-authored-by: Nikolaos Kasioumis <nikolaos.kasioumis@cern.ch>
Signed-off-by: Nikolaos Kasioumis <nikolaos.kasioumis@cern.ch>