Roll back to old PowerShell syntax highlighting

[daviwil]

• VSCode Version: 1.3.1
• OS Version: All

For the 1.3.0 release of VS Code we introduced a new syntax file for PowerShell which ended up having a few critical bugs. Since we keep finding more issues with the new syntax file I think it's probably good to revert back to the old one before finishing the 1.4 release. I know you're in lock down mode right now, but is there any possibility that we could revert for this release so that users aren't troubled by the issues anymore?

I'll go ahead and submit a PR, feel free to accept or reject based on what you decide.

Thanks!

/cc @aeschli @egamma

[daviwil]

Pull request here: #9923

[daviwil]

Thanks guys!