Add request() method

[thiagofigueiro]

This should return the most common information present in a HTTP request in a consistent manner. E.g.:

fake.request()
{
    scheme: 'http',
    version: '1.1',
    domain: 'www.example.com',
    port: 80,
    file_extension: 'jpg',
    content_type: 'image/jpeg',
    path: '/images/file.jpg',
    url: 'http://www.example.com/images/file.jpg',
}

Variations:

• scheme: http, https, spdy,
• version: 1.0, 1.1, 2.0
• domain: domain_name
• port: common ports associated with scheme
• file_extension: choose from mime_type_popular
• content_type: based on file_extension
• path: uri_path with file_name and file_extension matching content_type