Doctor doc scripts adapted to project needs

Doctor doc scripts adapted to project needs

Verification and building scripts have been adapted to serve Doctor
project specific needs. In Doctor we want to build design_docs in HTML
format, and requirement deliverable in HTML and PDF formats. We store
generated files in artifacts.opnfv.org

Jenkins master node may require installation of additional software as
new dependencies are here introduced (sphinx-build, sphinx numfig
extension, make, LaTeX).

JIRA: OCTO-67

Change-Id: Ieedbc3a01ba133575702cc7d5af6cc0bcee8a5d3
Signed-off-by: Carlos Goncalves <carlos.goncalves@neclab.eu>