Bring slides up to date with Fuel 5.1 and Juno

All slides updated to reflect the current state of Ceph support in Fuel and in
Mirantis OpenStack (some backlog items for Fuel were addressed, some bugs in
Nova were resolved, new features and fixes were added).

Slide aspect ratio changed from 4:3 to 16:9.

AsciiToSVG public REST service is down, Makefile and README.md updated to use
local a2s CLI instead.