importutils: initial release

* Cherry-picked from aa191a583772a77bfd86d8f4d608e7ada2fe613e.

Co-authored-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Reviewed-by: Tibor Simko <tibor.simko@cern.ch>
importutils: Python 2.4 support and test case

* Adds Python 2.4 support to importutils.

* Changes from using glob to regular expression for
  module matching.

* Adds test case.

Tested-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'master' into next

* master:
  importutils: Python 2.4 support and test case
  importutils: initial release

* Merge note: changed `webinterface_handler_flask` to use
  `related_name_re` instead of `_glob` as per Lars's updates.

Conflicts:
	modules/miscutil/lib/Makefile.am
	modules/miscutil/lib/importutils.py
importutils: Makefile clean up

* Removes doubly inserted importutils in Makefile.am.
Merge branch 'master' into next

* master:
  importutils: Makefile clean up

Conflicts:
	modules/miscutil/lib/Makefile.am
inveniomanage: initial release

* Adds initial implementation of `upgrader_manager` and
  `database_manager`.

* Adds new requirement for Flask-Script.  (addresses #1332)
BibFormat: manager initial release

* Adds support to bibformat_engine for Jinja2 templates.

* Extends Jinja2 context for bfe_* functions.

* Adds new variable CFG_BIBFORMAT_TEMPLATES_DIR.
WebComment: CmtSUBSCRIPTION model improvement
WebSearch: fix javascript block in /record pages
WebStyle: fix bug in pageheader template

* Fixes a small issue which would case an exception when rendering
  certain pages.

Reviewed-by: Jiri Kuncar <jiri.kuncar@cern.ch>
WebStyle: Flask request class customization

* Adds InvenioRequest as the default Flask request class with methods
  to allow for easier Flaskification of legacy modules.

Reviewed-by: Jiri Kuncar <jiri.kuncar@cern.ch>