WebLinkback: better URL title display

* Resolved XML entities in the title display
WebLinkback: better /linkbacks tab display

* Trackback URL displayed as link to simplify copy and paste

* Short trackback description displayed
WebLinkback: better global /linkbacks page

* Displays only records that are accessible by the user
WebLinkback: module optional

* Module can be disabled (closes #1245)
WebLinkback: better documentation
WebLinkback: minor improvement

* Renamed regression test method
WebLinkback: pending linkback notification emails

* Lists all pending linkbacks in one email (closes #1247)

* Enriched regression tests

* Enriched documentation
WebLinkback: fix for importing CFG_DATABASE values
dbquery: fix for importing CFG_DATABASE values
BibDocFile: fix check-md5 with bibdocfsinfo cache

* If the new bibdocfsinfo_cache functionality is enabled by
  setting CFG_BIBDOCFILE_ENABLE_BIBDOCFSINFO_CACHE = 1 in
  invenio(-local).conf, the md5s property of BibDoc objects
  was not correctly initialized and calling `bibdocfile --check-md5`
  would have failed with an unhanded exception.  This is fixed here
  by lazy initialization of the BibDoc.md5s property.  (closes #1249)

Tested-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'maint-1.1'

* maint-1.1:
  BibDocFile: fix check-md5 with bibdocfsinfo cache

Conflicts:
	modules/bibdocfile/lib/bibdocfile.py
textmarc2xmlmarc: remove content regexp check

* Removes content regexp check in textmarc2xmlmarc to allow
  controlfields.  This fixes failed regression test in BibMatch.
  (closes #1267)

Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibDocFile: revert md5 property patch

* Reverts md5 property patch 18c013cd7e511cb83d742e70bb0972e426ae0b0e
  that was defining only getter, not setter.  This caused problems
  during recreation of demo site.  (references #1249)

Reported-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
DocExtract: fix reference extractor unit tests

* Reference extractor's unit tests were not following Invenio convention,
  so running `inveniocfg --run-unit-tests` were not catching them.  This
  commit fixes the problem.
dateutils: fix for unit test suite

* Use absolute imports so that `inveniocfg --run-unit-tests` would
  run this test suite.
WebSearch: empty unit test suite for summarizer

* Fixes otherwise empty summarizer unit test suite so that
  `inveniocfg --run-unit-tests` would not complain about
  missing TEST_SUITE.
BibFormat: fix for fulltext file format

* Avoids exception for records containing only additional files
  and no main file.

Reviewed-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'maint-1.1'

* maint-1.1:
  BibFormat: fix for fulltext file format
Merge branch 'pglauner/better-weblinkback'

* pglauner/master-better-weblinkback:
  WebLinkback: pending linkback notification emails
  WebLinkback: minor improvement
  WebLinkback: better documentation
  WebLinkback: module optional
  WebLinkback: better global /linkbacks page
  WebLinkback: better /linkbacks tab display
  WebLinkback: better URL title display

* Merge note: besides solving conflicts, amended webstyle_templates slightly.

Conflicts:
	config/invenio.conf
	modules/webhelp/web/admin/howto/howto-run.webdoc
	modules/weblinkback/lib/weblinkback_regression_tests.py

Tested-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'ads_patches' of https://github.com/adsabs/invenio into ads_patches