Revision 1863289

Merge the r1859732 group from trunk:

 * r1859732, r1859734
   io: Implement the functions that check for node existence using the native
   Win32 APIs on Windows.
   Justification:
     - This allows us to remove the hack from r1833621 and properly handle
       reparse points on Windows irrespectively of the used APR version.
     - This improves the I/O performance by using only a single call to
       GetFileAttributes(), which is much faster than the generic stat
       implementations from APR 1.6.x and 1.7.x (the latter should be
       even more slower).
   Votes:
     +1: kotkov, rhuijben