Any configuration file changes and how to update should be listed here.

Config version 17
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 * Added config_log_colors

Config version 16
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 * Added config_commands_private_always
 * Renamed config_listenregex to config_commands_listenregex
 * Renamed config_unknown_commands to config_feedback_unknown_commands.


Config version 15
-----------------
This file was added at this point. To convert from older versions to this
one, please read example config and add what is missing.