Bind XSD, DTD with CodeLens

[angelozerr]

Bind XSD, DTD with CodeLens

See redhat-developer/vscode-xml#395

Signed-off-by: azerr azerr@redhat.com

[angelozerr]

@BoykoAlex pay attention this PR will break the API of command (IDelegateCommandHandler). Now we will have the shared settings in the parameter:

public interface IDelegateCommandHandler {

		/**
		 * Executes a command
		 * 
		 * @param params        command execution parameters
		 * @param sharedSettings the shared settings.
		 * @param cancelChecker check if cancel has been requested
		 * @return the result of the command
		 * @throws Exception the unhandled exception will be wrapped in
		 *                   <code>org.eclipse.lsp4j.jsonrpc.ResponseErrorException</code>
		 *                   and be wired back to the JSON-RPC protocol caller
		 */
		Object executeCommand(ExecuteCommandParams params, SharedSettings sharedSettings, CancelChecker cancelChecker) throws Exception;
	}

[datho7561]

The code looks pretty good and it works great!

I think we should add a file in docs/ that explains what the client needs to implement in order to support these CodeLens properly.

It would be nice if the code actions that add the XML to bind to the schema respected the formatting settings, but this could be handled in a different PR.