Improve Tutorial Documentation and Instructions for End-to-End Flows

[VRamakrishna]

The set of instructions for the different flows (https://labs.hyperledger.org/weaver-dlt-interoperability/docs/external/getting-started/interop/overview) is a very dry read, even though one can run and test the flows/modes using the given instructions. We need to:

• Represent these flows with examples that users can relate to (copying some ledger info, exchanging some asset, etc.)
• Create suitable illustrations in the doc pages
• Change names of keys, values, and assets to something meaningful (unlike a, Arcturus, etc.): this will involve changing both the configurations within the samples folder and updating the doc pages suitably.

[VRamakrishna]

I will try to create the new diagrams and content for the tutorial docs before the Cacti merge. Name changes can wait until the merge.