Rename es_quirk annotation to quirk

[sethmlarson]

Since we're moving to support general OpenAPI I think we should drop the es_ prefix for the esQuirk annotation. I'm unsure if any code generators are relying on it serializing directly into schema.json this way, if so we can keep it in the final schema.json until we all move away from this.

[swallez]

Yes, we can rename it. Something I've planned to do in the Java generator (but still todo) is to have a list of quirks that have been implemented along with a hash of their descriptions. This will allow tracking new quirks and also changes in their description (which may have some impacts on code generation).