Add Clinical Quality Language (CQL)

[antvaset]

Adding support for the Clinical Quality Language, a high-level language used in health IT with the focus on clinical quality measures and clinical decision support.

Checklist:

• [x] I am adding a new language.
  • [x] The extension of the new language is used in hundreds of repositories on GitHub.com.
  • Search results for each extension:
    • https://github.com/search?type=code&q=NOT+is%3Afork+path%3A*.cql+"context%2FPatient"
  • [x] I have included a real-world usage sample for all extensions added in this PR:
  • I wrote the samples specifically for the PR and I am happy for them to be included under the MIT license that covers Linguist.
  • [x] I have included a syntax highlighting grammar: https://github.com/cqframework/vscode-cql/blob/master/syntaxes/cql.tmLanguage.json
  • [x] I have added a color
  • Hex value: #105eab
  • Rationale: This is the color used by the CQL specification website.

[antvaset]

Hi @lildude, thank you for having a look at this! Just wanted to highlight that CQL is used on GitHub by folks like Google (1, 2), IBM (3), WHO (4), and CMS (5). It's an HL7 and ANSI normative standard and is important in health IT together with FHIR. Perhaps you could reconsider the "pending popularity" status? What do you think? :)

[lildude]

Perhaps you could reconsider the "pending popularity" status? What do you think? :)

No. This would set a precident that defeats the point of having usage requirements which I'd need to defend time and time again.

I only reached this conclusion based on your search query and saw that the creator of the language has a significant impact on the usage which isn't really surprising as it's in the creator's best interests to promote their language as much as possible. Excluding them drops the usage significantly.

Things don't look far off inclusion so things might be high enough when it comes to reviewing pending PRs when I make the next release (likely to be the end of August/early September) or the one after that if things are really as popular as you're suggesting.