Add User generator that accepts arguments

[ashishra0]

Issue #1671

Description:

Added a user class method to the Internet class which takes in multiple arguments that the Internet class already provides and returns a desired hash. For E.g.

user = Faker::Internet.user('name', 'email', password')
=> {'name' => 'John Doe', 'email' => 'fake_email@test.com', 'password' => 'pass123' }