Fixes a (possible) stack overflow

The stack overflow occurred in debug mode, due to the recurrent deletion of the
nodes of the binary tree (scenario: lots of nodes with same CRC & hash).

This is rather a quick-and-dirty fix, as I don't really know how the tree
itself is used from the outside (what's the owner concept? not clear).
The fix suppresses the recurrence and uses loops instead.
Adds VS2010 solution and project files and pthreads property sheet

The property sheet allows quick adjustment of the pthreads path.