docs: extend README.md page

- feature highlights
- contents page

Signed-off-by: David Scott <dave.scott@citrix.com>
docs: include the architecture diagrams

Signed-off-by: David Scott <dave.scott@citrix.com>
doc: describe diagram

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #10 from djs55/lots-of-docs

Add architecture diagram