Implement missing console commands

Help ToggleDebugText (TDT) ToggleDialogueStats (TDS) ToggleGrid (TG) ToggleScriptOutput (TSO) ToggleStats (TST) ToggleTextureString (TTS)

(RM-1421 from redmine: created on 2014-06-08 by rot tor, , relates #2780 (closed), duplicates #1607 (closed))