Merge branch 'ef/win32-dirent'

Merge branch 'ef/win32-dirent'

* ef/win32-dirent:
  win32: use our own dirent.h
  msvc: opendir: handle paths ending with a slash
  win32: dirent: handle errors
  msvc: opendir: do not start the search
  msvc: opendir: allocate enough memory
  msvc: opendir: fix malloc-failure

Conflicts:
	Makefile