Embedded schema is supported!

The generator now supports arbitrarily embedded schema such as 
{ username: 'name',
  contacts: {
    address: 'address',
    phones: {
      mobile: 'telephone',
      work: 'telephone'
    }
  }
}
There is an example schema in file 'schema_user.json'. To generate docs using this schema, run command "node index.js --size=<size> --schema=schema_user.json". Thanks!