named Mute Groups and DCA

[schulz-alexander]

@flipfi suggested

In the future, if DCA and Mute Groups support custom names, those names could be displayed in the Config screen instead of just the group numbers, making channel assignments easier to identify at a glance.

Todo

• Mute Groups and DCA should have a name -> new Mixerparameters: MUTE_GROUP_NAME and DCA_NAME
• show them in config page and every else where they are used