Add task generator.

[namusyaka]

ref #1200

$ padrino g task
Usage:
  padrino-gen task [name]

Options:
  -r, [--root=ROOT]                # The root destination
                                   # Default: .
  -d, [--description=DESCRIPTION]  # The description of your application task
  -n, [--namespace=NAMESPACE]      # The namespace of your application task

Description:

    padrino-gen task generates a new task file.

How about this one?

[nesquena]

Looks good to me. Thanks @namusyaka!

[ujifgc]

Does it close #1200 ?

[namusyaka]

Yeah, closed.