Response format with pagination and Swagger

Ok, guys. I think one response format would be the best way. Will add it to the next release.

@DaVarga Another part of the workaround (in addition to the interceptor) is Swagger meta overriding (possible after #113).

1. Define generic class for the response model (similar to GetManyDefaultResponse interface but with optional props):

   class GetManyResponse<Entity> {
     @ApiModelProperty({ type: Object, isArray: true }) // will be overwritten
     public data: Entity[];
   
     @ApiModelPropertyOptional()
     public count?: number;
   // ...
   

2. Define a factory function:

   type Entity = Function;
   
   function getManyResponseFor(type: Entity): typeof GetManyResponse {
     class GetManyResponseForEntity<Entity> extends GetManyResponse<Entity> {
       @ApiModelProperty({ type, isArray: true })
       public data: Entity[];
     }
     Object.defineProperty(GetManyResponseForEntity, 'name', {
       value: `GetManyResponseFor${type.name}`,
     });
   
     return GetManyResponseForEntity;
   }
   

3. Add ApiOkResponse decorator to options:

   @Crud({
     model: {
       type: Company,
     },
     routes: {
       getManyBase: {
         interceptors: [GetManyResponseInterceptor],
         decorators: [
           ApiOkResponse({ type: getManyResponseFor(Company) }),
   // ...
   

Or as an alternative, simply pass total count as X-Total-Count header in an interceptor. Then no need to redefine Swagger meta.