Replace the WDL language grammar

[claymcleod]

This PR updates support for the WDL to the latest version (v1.2).

Description

We've written the grammar from scratch to be compliant with the latest version of WDL—currently, the grammar used in linguist is around 6 years old (and represents a very old version of WDL).

A list of some (but not all) improvements being:

• Added all keywords (e.g., requirements).
• Shell highlighting within command blocks.
• Better semantic classification of different keywords.

Checklist:

• I am changing the source of a syntax highlighting grammar
  • Old: https://github.com/broadinstitute/wdl-sublime-syntax-highlighter
  • New: https://github.com/stjude-rust-labs/sprocket-vscode

(From the I am adding a new language of the template. section, as I'm adding a new example)

• I have included a real-world usage sample for all extensions added in this PR:
  • Sample source(s):
    • fq.wdl
  • Sample license(s): MIT

[lildude]

Please do not change the samples. They are used to train the classifier and there will almost always be files on GitHub using older syntax.

If you want to help detect newer syntax, add more samples.

[claymcleod]

Okay, I've reverted those samples and added a new one! Let me know what you think, @lildude.

[lildude]

Please also replace your sample with a real world example and update the template to state where it comes from and the license of the sample.

[claymcleod]

Please also replace your sample with a real world example and update the template to state where it comes from and the license of the sample.

This should be addressed: I added a new, real-world example and also added the license to the template for the PR and the header of that sample.

[lildude]

The test failure suggests you might not have used the documented method of replacing the grammar as the script sorts the submodules.

Please use the script as documented. You can replace the grammar with itself using the script.

[claymcleod]

Okay, I think I've resolved this now—I had used the script, but had done some spelunking on the codebase beforehand to try to understand how it worked (in unstaged changes).

I checked out a fresh version of the repo, applied my changes, and then got bundle exec rake running with no errors.

[lildude]

LGTM. Thanks.

Note: this PR will not be merged until close to when the next release is made. See here for more details.