ABI 0.2 (part 1/2)

[namesty]

This PR includes:

• New ABI types
• Usage examples
• New JSONSchema
• Documentation on introduced concepts, decisions made, future plans

[dOrgJelli]

Do we want to target a different branch that will act as more of a "staging" branch for wrap 0.2? I think wrap-0-2 is currently pretty heavily under development with the work @nerfZael and @Niraj-Kamdar are doing at the moment. Maybe we should:

1. create a wrap-0.2-dev branch from master.
2. rename the wrap-0-2 branch you all are working in to something more specific to the standards you all are working on.

[Niraj-Kamdar]

I have left some comments.

[Niraj-Kamdar]

What if we use IPFS hash of the abi as id?
It's guaranteed to be unique and since content addressable no need to embed the imported abi.

[dOrgJelli]

The goal of the "id" is to be a (1) small in size & (2) efficient to lookup (i.e. strcmp). The URI does not satisfy these things in my opinion.

[Niraj-Kamdar]

I believe it has its own benefits as I discussed and we should compare both and see which is a better way going forward.

[dOrgJelli]

Responded @Niraj-Kamdar, would you feel comfortable approving in its current state?