Add command and additionalTextEdits to CompeltionItem.

[akosyakov]

It is required for the LSP: TypeFox/monaco-languageclient#39.

It looks like the conversion should be done here:
https://github.com/Microsoft/vscode/blob/63efefc7c279e7c963d223123d7248137034252a/src/vs/editor/standalone/browser/standaloneLanguages.ts#L626

@alexandrudima is there a reason not doing it?

[alexdima]

@akosyakov The Monaco Editor API CompletionItemProvider tries to keep on par with the vscode API one. If they fall out of sync, it is only because somebody changed the vscode one, but forgot to change the Monaco Editor one.

[akosyakov]

Would it be possible to sync them and publish a new patch version of monaco-editor?

[alexdima]

PR welcome.

[akosyakov]

@alexandrudima ok, i am looking into it