launch.json template should switch from 'command.' to 'command:'

[gregg-miskelly]

In VS Code 1.10, the ${command. was deprecated, and gives a warning to switch to ${command:. But our templates still use the '.' version.

[chuckries]

Do we need to update our minimum VS Code version with this fix as well?

[gregg-miskelly]

I think so. We will be doing so with the vsdbg work anyway, so I don't see any downside of doing that.