Quadtree: correct OpenMP parallelism
Quadtree: correct OpenMP parallelism

The problem is that the STL vector 'array' is being used in multiple threads in
parallel. Give each thread its own vector and merge the result into 'array'.

Signed-off-by: Steven Noonan <4068f0880b399410602d694b3cc711c8a8f4727e@uplinklabs.net>

tycho/crisscross,tycho/crisscross,tycho/crisscross