Better Chat Mute is a simple mute system, made for use with Better Chat. Using with Better Chat is intended, but the plugin can be used standalone as well.
/mute <player|steamid> [reason] - Mute player permanently
/mute <player|steamid> <time: 1d1h1m1s> [reason] - Mute player temporarily
/unmute <player|steamid> -- Unmutes player
/mutelist - Show players that are muted
/toggleglobalmute - Disable chat for every player without the