Add a faker:generate command for command line usage.

I like this fake data generate, but I need the data also for static generation, e.g. for importing into the database. Instead of always write a new php script, to generate the data I wrote a console command to use the faker on the command line.

See the [readme](https://github.com/tristanlins/Faker/tree/feature/command-line#command-line-usage) for a usage example.