Added newer Fedora release versions; linked to Fedora EoL page; removed the GlusterD2 section given that it is no longer under active development within the project.
- Fixes to Markdown syntax for code highlight
- `console` is used to highlight shell sessions
- Uniform char used for shell "#" in code blocks.
- Snapshot page styles fixed
- Replica 2 examples changed to Replica 3
Signed-off-by: Aravinda VK <avishwan@redhat.com>