C# extension should provide launch.json templates

[gregg-miskelly]

With the November 2016 release of VS Code, there is now support for launch.json templates. See microsoft/vscode#16937 for examples.

This is less interesting for the C# extension since we normally generate launch.json, but it is useful in a few cases --

• Users with multiple launch projects that would like multiple launch configurations
• Adding templates for SSH

We should add new templates for local launch, local attach, ssh launch and ssh attach.

[WardenGnaw]

Do we want to dynamically create the configuration snippets or just list all possible configurations?

If it is dynamically created, we will be able to filter out non-usable configurations. This also reduces the amount of non-usable choices for the user.

The image below shows how crowded the list becomes with a couple of extensions installed.

If we decide to add 4 configurations multiplied by 2 for Windows/Linux differences it will get crowded.

Sadly, creating snippets via a command, like initial configurations, does not work: microsoft/vscode#23961

[gregg-miskelly]

Here are the node snippets as an example: https://github.com/Microsoft/vscode-node-debug/blob/master/package.json#L117

[gregg-miskelly]

@WardenGnaw should we leave this open to react to a possible VS Code fix in the future to make this better? Or should we close this for now?

[WardenGnaw]

I think we can close this one and then create a new issue asking for "dynamic launch.json templates with comments". That can be worked on once microsoft/vscode#23961 is completed.