Log Message:
Update to apr version 1.3.7, which, other than 1.3.5, is still downloadable.

Changes since 1.3.5:
 - On Linux/hppa flock() returns EAGAIN instead of EWOULDBLOCK. This
   causes proc mutex failures.
 - Set CLOEXEC flags where appropriate. Either use new O_CLOEXEC flag and
   associated functions, such as dup3(), accept4(), epoll_create1() etc.,
   or simply set CLOEXEC flag using fcntl().
 - More elaborate detection for dup3(), accept4() and epoll_create1().