Redesigned CForest to minimize changes to asymptotically optimal planner...

...s it uses. Fix bug in benchmarking that caused huge log files. Added option for tree pruning in RRT*
It is a matter of efficiency. It could happen that this thread finds a better solution, but not better than one found that the other threads. This thread, in fact, will most probably find better paths while adding shared states. But those paths are probably not better than the one which is being shared.  Actually, you are using prune_ iin place of what I called isCForest_ and isCForest_ was not only for prunning operations. I am afraid there is some misunderstanding here.