Fix incorrect error message in create server

Fixes #5
Rename package kamaki.cli.command_tree --> cmdtree
Rename package  kamaki.cli.commands --> cmds
Rename module kamaki.cli.command_shell --> shell
Rename module kamaki.cli.one_command --> one_cmd
Rename class _command_init --> CommandInit

Class is located at kamaki.cli.cmds
Merge classes _optional_output_cmd, _optional_json

New class is called "OptionalOutput"
Old and new classes were/are located at kamaki.cli.cmds
Rename classes _id/name_filter --> [ID/Name]Filter

Both classes are located in kamaki.cli.cmds
Update kamaki.cli.cmds.astakos class names to pep8

Renames:
_init_synnefo_astakosclient --> _AstakosInit
_project_action --> _ProjectAction
_application_action --> _ApplicationAction
_membership_action --> _MembershipAction