Versioned `yaml` problem definition schemas

[amkrajewski]

• We should have a problem definition (akin to this part of README) in problemSchema.yaml that includes schema version field.
• All problem statements should also include the problem schama version they follow.
• The ammap code should verify that the problem is compatible with the current code version. It should give a warning if any depreciation is planned in newer version and meaningful error if anything cannot be processed.