errorlib: context support in sentry

* Introduces support for HTTP, and user context in sentry, by
  exploiting information provided in req object when available.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibEdit: user name in BibSched column

Signed-off-by: Javier Martin Montull <javier.martin.montull@cern.ch>
WebSearch: filtering of citation tab counts

* Does not filter anymore by collection:citeable in the counts displayed
  next to the tab title.
BibAuthorID: get_arxiv_url() fix

* Fixes generation of arXiv URL.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
Revert "BibRank: index all collections"

This reverts commit 89c931989670d622324c13c60d26cbf6f9209bf1.
Revert "BibRank: faster indexing"

This reverts commit e6f5e066a4e0a19f6cf8ef596618af68e8de9564.
BibRank: left over cites for deleted records

* Removes the recid from the information dictionary when computing
  citations so that references done via 999C50 are ignored for
  record not in the selected collections.
BibSched: tracebacks with context
installation: location of demo_table_jui.css

* Fixes location of demo_table_jui.css by explicitly referencing last
  git tag that contained the file.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>

Conflicts:
	Makefile.am
errorlib: undefined collect_user_info
WebSearch: debug text for citation log
WebSearch: overwritten recid variable in citation tab