message: Tweak error message about missing generator
diff: @@ -422,7 +422,8 @@ export class CMakeTools implements vscode.Disposable, api.CMakeToolsAPI {
  });
  } else if (e instanceof NoGeneratorError) {
  vscode.window.showErrorMessage(
  - `CMake Tools was unable to determine the Generator to use for the chosen kit.`);
  + `Unable to determine what CMake generator to use. ` +
  + `Please install or configure a preferred generator, or update settings.json or your Kit configuration.`);
  } else {
  throw e;
  }
  