stop using IndexTarget pointers which are never freed

stop using IndexTarget pointers which are never freed

Creating and passing around a bunch of pointers of IndexTargets (and of
a vector of pointers of IndexTargets) is probably done to avoid the
'costly' copy of container, but we are really not in a timecritical
operation here and move semantics will help us even further in the
future. On the other hand we never do a proper cleanup of these
pointers, which is very dirty, even if structures aren't that big…

The changes will effecting many items only effect our own hidden class,
so we can do that without fearing breaking interfaces or anything.

Git-Dch: Ignore