YQL-21111: Introduce feature registry

A feature registry lets us to reference features by name, rather than a concrete langver.
It makes easier to find feature references and releasing incubating features (under max
langver during the development). Features are described at
`yql/essentials/data/language/features.json` and the C++ code is generated. The unit
`feature.h` also introduces a convenience functions to check a feature availability and
emit a standard error message. All features in the translator where replaced with named.
commit_hash:c47f540536212a65f7bc5e8dc6051e73d006be8d

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