Add default_member_permissions and contexts fields to application commands

[wouterdedroog]

Summary

Add default_member_permissions and contexts field to application commands to allow disabling of application commands in DMs and more precise setting of permissions.

---

Added

• Added default_member_permissions and contexts to register_application_command and edit_application_command
• Added default_member_permissions and contexts to create_guild_command, create_global_command, edit_guild_command and edit_global_command.

Changed

Deprecated

Nothing yet, although I'd recommend removing/deprecating default_permission in favour of default_member_permissions. I could incorporate this in my PR if desired, but we can also decide to keep this for now.

Removed

Fixed

• Implement fix as suggested by Fix edit_application_command with global scope. #253

[swarley]

Thanks!