Added substitutions for ^, <, >, |, &, for use in command list items.
Silent designator is removed and replaced with new COMMANDQ list entry. Also, %}%NUL can now be used at the end of the command to quiet output.
Existing command items within a list will need to be updated to the new format or they will not execute.
Moved main menu .xml generate / export tasks to tweaks.mst.