added spigot subcommand blocking system

src/main/resources/config.yml

@@ -1,6 +1,7 @@
 messages:
   prefix: "CommandWhitelist > "
   command-denied: "No such command."
+  subcommand-denied: "You cannot use this subcommand"
   no-permission: "&cYou don't have permission to do this."
   no-such-subcommand: "&cNo subcommand by that name."
   config-reloaded: "&eConfiguration reloaded."
@@ -30,4 +31,11 @@ commands:
     - warp
   # commandwhitelist.commands.example
   example:
-    - example
+    - example
+
+tabcompletions:
+  # This one is working as a blacklist. Player will not be able
+  # to see/use listed subcommands unless they have specified permission
+  # commandwhitelist.subcommands.default
+  default:
+    - help about