Added support for: reject status code and message; context.statusCode.

[mrauhu]

Greetings, Guillaume @Akryum.

In this pull request I added support for:

• reject code set status code and message appends to body:

  // no matched routes
  if (!matchedComponents.length) {
    reject({ code: 404, message: 'Not found' })
  }

• context.statusCode and example of usage with wildcard * path for creating custom 404 error.

Best wishes,
Sergey.