Add isupport to plugins

rowbot

@@ -475,6 +475,22 @@ on_sys_init_999_welcome() {
   get_option chan ""
 }
 
+on_msg_005_welcome() {
+  declare -gA isupport
+  local param key value
+
+  for param in "${args[@]:1:${#args[@]}-2}"; do
+    # This is a valid assignment, not a comparison.
+    # shellcheck disable=SC1097
+    IFS== read -r key value <<< "$param"
+    # While isupport is unused, it's still there in case later code wants to
+    # use it.
+    # shellcheck disable=SC2034
+    isupport[$key]=$value
+    debug "isupport: %s = %s" "$key" "$value"
+  done
+}
+
 on_sys_register_999_welcome() {
   if [[ ${config[chan]} ]]; then
     irc_join "${config[chan]}"
@@ -587,7 +603,7 @@ irc_on_004() {
 }
 
 irc_on_005() {
-  log_debug "received inotify specification: ${msg_args[*]}"
+  log_debug "received inotify specification: ${msg_args[*]:1}"
 }
 
 irc_on_250() {