Escape commas in option flag arguments

[marler8997]

I think this might address the issue with dlang/dmd#7777 but I'm not 100% sure.

[dlang-bot]

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[wilzbach]

escapeDdoc already exists ;-)

[marler8997]

nice...was eerily similar to the new function I added :)

[wilzbach]

Thanks!
Sorry that I haven't been able to help you earlier - I was occupied with our Munich Meetup :/