Add commands

[hallowatcher]

Description

Commands like /join [channel] are missing

Passing criteria

• /addfriend [user]
• /delfriend [user]
• /away [message]
• /chat [user] 61797cb
• /clear 61797cb
• /j [channel] or /join [channel] 2ed4e68
• /p or /part 2ed4e68
• /me [action] 087e981
• /msg [user] [msg]

[hallowatcher]

Refer to https://osu.ppy.sh/help/wiki/Chat_Console/ for complete list of commands