More additions to .rubocop.yml, minor code tweaks

Data/Scripts/001_Technical/005_PluginManager.rb

@@ -726,8 +726,8 @@ module PluginManager
         end
       end
     end
-    echoln ""
     if scripts.length > 0
+      echoln ""
       Console.echo_h2("Successfully loaded #{scripts.length} plugin(s)", text: :green)
     else
       Console.echo_h2("No plugins found", text: :green)

Data/Scripts/007_Objects and windows/011_Messages.rb

@@ -522,6 +522,7 @@ def pbMessageDisplay(msgwindow, message, letterbyletter = true, commandProc = ni
   signWaitTime = Graphics.frame_rate / 2
   haveSpecialClose = false
   specialCloseSE = ""
+  startSE = nil
   controls.length.times do |i|
     control = controls[i][0]
     param = controls[i][1]