Triggered by the deployment failure that was caused by an invisible Unicode character in a rule's metadata.json.
This PR implements three conceptual changes:
- make the deployment parse error more informative
- prohibit the use of non-ASCII characters in the metadata.json files
- remove the existing non-ASCII characters from the existing rules
* Generate description and metadata for rules with no language, so that they get indexed.
* Index rules with different types in language specializations.
* Improve validation to reject new rules with no language specialization (i.e. only a predefined set of such rules is allowed because they were imported from Jira and kept for historical purposes).
* Write smaller JSON files, reduce their size by 30%.
* Improve test coverage of CLI application.
