add `/cw subcommand add <subcommands>` & `/cw subcommand remove <subcommands>`

[Huge-mistake]

Is your feature request related to a problem? Please describe.
Sometimes I can't modify the config.yml directly, and I hope there's a command to edit subcommands directly.

Describe the solution you'd like
add /cw subcommand add <subcommands>
/cw subcommand remove <subcommands>

Describe alternatives you've considered
add /cw sub add <subcommands>
/cw sub remove <subcommands>

[marioogg]

you know what, that's a good idea i'll try to make a pr for this.