Implement debug target launching in integrated terminal

[weinand]

This is the frontend implementation for microsoft/vscode-debugadapter-node#47.
The implementation for node-debug is this: microsoft/vscode-node-debug#85
The implementation would be based on #9957.

[weinand]

@isidorn I've added a first cut of this to the debug protocol and node-debug.
If you pass a supportsRunInTerminalRequest with value true to the InitializeRequest, node_debug will call the runInTerminalRequest on VS Code. See https://github.com/Microsoft/vscode/blob/master/src/vs/workbench/parts/debug/node/v8Protocol.ts#L69

[Tyriar]

Keep in mind that the command sent would be sent to the currently configured shell (bash, zsh, powershell, cmd, etc.).

[DanTup]

@weinand I'm not familiar with/haven't installed the Insiders builds yet - that change is in master, does that mean we can try it out in insiders from tomorrow? :)

(Also, how releases are cut; presumably not from master if there's in-progress stuff like this that might not make the release? I searched but couldn't find any info on the relationship between branches/releases/etc.)

[weinand]

@DanTup you can try this as soon as this issue is closed. Currently the VS Code side of things is missing (and we are not sure that this will be implemented in the August release).

Releases are cut from Master. In-progress stuff will either be disabled or just not mentioned in the release notes.