Clean up, fix, and tweak the spellcasting dialog

- Includes new status effect images for the forcecage and for hypothetical inverses of dumbfound and magic resistance, as well as icons for the whole-party statuses.

osx/dialogxml/dialog.cpp

@@ -1217,6 +1217,7 @@ bool cDialog::addLabelFor(std::string key, std::string label, eLabelPos where, s
 	if(bg == BG_DARK && dynamic_cast<cButton*>(&ctrl) != NULL)
 		labelCtrl->setColour(defTextClr);
 	else labelCtrl->setColour(ctrl.getColour());
+	ctrl.setLabelCtrl(labelCtrl);
 	return add(labelCtrl, labelRect, key);
 }