installation: Flask-Registry version update

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

* Installing the npm dependencies globally, less configuration.

* Forcing non interactive versions of apt-get and make-ssl-cert.

* Fixing uglifyjs to uglify-js, different projects.

* Ignoring stuff from bower.io.

* Can be used by the docker container greut/invenio:test to test a
  particular branch just like travis would.

Signed-off-by: Yoan Blanc <yoan.blanc@cern.ch>