Roundtrip JSON serialization/deserialization

[sneakers-the-rat]

fix: #17

(will write description after draft complete)

• Separate the core_schema generation from the json schema generation
• Allow all array interface proxy types to be dumped to json
• control over serialization
  • round_trip to control including extra metadata?
  • use context to control whether we dump the whole array or just the proxy info

todo

• testing: test instantiation from the roundtrip json dict
• testing: test absolute paths
• testing: test relative_to paths
• testing: test mark interface

[coveralls]

Pull Request Test Coverage Report for Build 11005171737

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 329 of 329 (100.0%) changed or added relevant lines in 11 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.9%) to 99.231%

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Totals
Change from base Build 10693070848:	0.9%
Covered Lines:	1162
Relevant Lines:	1171

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💛 - Coveralls