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>
Merge pull request #1954 from kaplun/fix-install-demo_table_jui

installation: location of demo_table_jui.css
inveniogc: clean up gc tasks

* Removes obsolete gc tasks (such as bibedit tmp files, bibreformat).

* If CFG_INSPIRE_SITE=1, disables for INSPIRE non related gc tasks
  (BibSword, BibEncode...).

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