installation: Flask-Gravatar version 0.4.0

* NOTE: Updates version of Flask-Gravatar. Please run
  `pip install Flask-Gravatar==0.4.0 --upgrade`.

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
installation: Jinja2 version 2.7.1

* NOTE: Updates version of Jinja2. Please run
  `pip install Jinja2==2.7.1 --upgrade`.

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
mailutils: fix unicode error in templates

* Addresses issue with UTF-8/unicode encoding.  (addresses #1598)

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
SQLAlchemy: autodiscover modules on demand

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
importutils: ignore exceptions option addition

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
WebStyle: blueprint loading using importutils

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
BibWorkflow: specific worker loading

* Loads only specific worker using `import_string`.

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