Update kamaki.cli.cmds.network class names (pep8)

Renames:
_init_network --> _NetworkInit
_port_wait --> _PortWait
Update kamaki.cli.cmds.pithos class names (pep8)

Renames:
_pithos_init --> _PithosInit
_pithos_account --> _PithosAccount
_pithos_container --> _PithosContainer
_source_destination --> _PithosFromTo
_pithos_group --> _PithosGroup