cmd_area_attack_tweak.lua: make CTRL+Area_attack consistent with bomber behaviour

Adding additional command using SHIFT (after CTRL+Area_attack) will make unit continue to queue instead of going to next target.

Also removed "http://springrts.com/mantis/view.php?id=4351" fix since it was reported as resolved.
And some cleanup to make stuff (only abit) less messy.