Java 8 -16 | Bukkit 1.8 - 1.17 | various fixes.

Java 8 and above compatibility,　 Backwerds Compatible from 1.8 - 1.17
288 -291 - UltraCommand - You don't have permission for this command,
　　　　　If you believe you should ask an admin for the following permission. ()
206 - 207 - UltraCommand - Permissions to LowerCase (for Linux/BSD)
142 - 143 - UltraCommand - Saved Successfully
300 - 301 - UltraCommandExecutor - Commands configuration saved successfully.
272 - 273 - UltraCommandExecutor - Commands configuration has been reloaded.
265 - 266 - UltraCommandExecutor - There are no console commands for this command.
261 - 262 - UltraCommandExecutor - There are no player commands for this command.
257 - 258 - UltraCommandExecutor - There is no chat defined for this command.
157 - 158 - UltraCommandExecutor - Error: addCustomCommand returned false.
150 - 151 - UltraCommandExecutor - already exists.
040 - 041 - UltraCommandExecutor - You don't have permission for this command,
　　　　　 If you believe you should ask an admin for the following
　　　　　 permission. (ultracommand.configure)

compatibility, command priority and command expectations fix

compatibility down to Bukkit, Spigot and Paper 1.8 and above.
changed how and when the plugin should be loaded on startup to give UltraCommand full control over all commands you may want to create, for example you can create custom command overrides to replace any existing command! e.g. you can easily cover /op with the following example:
/ud add text op &6&l&oExamplePrefix &f&l&o> &cYou can NOT use this command
/ud add pcmd op me Just attempted to run /op
/uc add text minecraft:op &6&l&oExamplePrefix &f&l&o> &cNice try, but you can NOT use this command even with a prefix.
/ud add pcmd minecraft:op me Just attempted to run /minecraft:op
Those 2 basic commands will block the /op command from being used even by your admins and report in chat what they did, of course you can customize this to your likening.
don't forget that each command created generates it's own permission, so be sure to give the permission node for your new commands to everyone. (ultracommand.commands.op | ultracommand.commands.minecraft:op)

[142-145] updated messages: "Successfully Saved", "Failed to Save", "Commands configuration successfully saved." and fixed possiable expectations when using commands:
/uc list - list all custom commands
/uc list (Returns weather or not there are Chat Commands, Player Commands or Console Commands and what they are if they exist)
/uc reload - reload all custom commands (usefull after editing your commands via the commands.yml)

UltraCommand

UltraCommand PreCompiled and Ready for use with Bukkit, Spigot, paper and likely all it's forks