Add legibility improvements hightlight state of the flow

See merge request !4

Use color to ephasize connection state with red hues indicating
no login or unauthorized and green hues indicated authentected.

This makes it easy to distinguish parts of the flow.

Add session state note for SAML handshake and authn state note for JS flow.

Update xdmod_ood_integration.md to remove communication between xdmod and OOD, as previously incorrectly shown 

Update mermaid-diagram-2023-01-23-131655.png

See merge request !2

Update README.md

See merge request !1