Correct ports used by Hadoop for Savanna

Added more ports to the Reference Architecture page with their description.
Also explicitly marked ports which are required for Savanna to work
properly and the ports required for post-deployment check to pass.

Closes-Bug: #1268612
Change-Id: I0e9fcdfb753ff8771a4e44f143fe5cd44e794239
Inkscape could be installed with apt

So why not suggest to do it?

Change-Id: I90d84204d7f9ff8f8e97706bb94dbab23ad14b1c
Merge "Inkscape could be installed with apt"