restful: initial release
restful: initial release

* Adds Flask-Restful initialization.

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

NOTE: beware, patch amended by Tibor to use new file names

inveniosoftware/invenio-base,inveniosoftware/invenio-base,tiborsimko/invenio-base,tiborsimko/invenio-base