message: Rename WhitelistController.toMongooseObjectId
  ...to prepareWhitelistUserData, because the "toMongooseObjectId" might
  be somewhat more confusing since the method doesn't actually return a
  single ObjectId object, but a filtered version of the given whitelistUser.
diff: @@ -102,7 +102,7 @@ export class WhitelistController {
  async addWhitelistUser(@Body() whitelistUser: IWhitelistUser) {
  let savedWhitelistUser;
  try {
  - savedWhitelistUser = await new WhitelistUser(this.toMongooseObjectId(whitelistUser)).save();
  + savedWhitelistUser = await new WhitelistUser(this.prepareWhitelistUserData(whitelistUser)).save();
  } catch (err) {
  throw new BadRequestError(errorCodes.whitelist.duplicateWhitelistUser.text);
  }
  @@ -144,7 +144,7 @@ export class WhitelistController {
  const foundWhitelistUser = await WhitelistUser.findById(id);
  try {
  updatedWhitelistUser = await WhitelistUser.findOneAndUpdate(
  - this.toMongooseObjectId(whitelistUser),
  + this.prepareWhitelistUserData(whitelistUser),
  {'new': true});
  } catch (err) {
  throw new BadRequestError(errorCodes.whitelist.duplicateWhitelistUser.text);
  @@ -199,7 +199,7 @@ export class WhitelistController {
  }
  }
  - toMongooseObjectId(whitelistUser: IWhitelistUser) {
  + prepareWhitelistUserData(whitelistUser: IWhitelistUser) {
  return {
  _id: whitelistUser._id,
  firstName: whitelistUser.firstName,
  