PoC: Add built-in CCF contract with encode function

[turbolent]

Work towards #3637

Description

Add a new built-in contract CCF, which allows encoding an exportable value to .

The parameter of encode is a reference, so it can accept both structs and resources, and supports move-semantics of resources (i.e. does not consume the passed resource-kinded value)

For now this is a PoC showing how this could be done.

### TODO
- [ ] Determine interest and use-cases
- [ ] Add more tests
- [ ] Decode function?

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• [x] Targeted PR against master branch
• [x] Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• [x] Code follows the standards mentioned here
• [x] Updated relevant documentation
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• [x] Added appropriate labels