Don't rely on the presence of stdbool.h and inttypes.h headers for utf8proc.

* configure.ac: Check for stdbool.h and inttypes.h.
* subversion/libsvn_subr/utf8proc/utf8proc.h:
   Include stdbool.h and inttypes.h only if we know they're available.
   Otherwise, use typedefs based on APR's sized types.
* subversion/libsvn_subr/utf8proc.c:
   Move the include of utf8proc.c after svn_private_config.h, so that the
   presence symbols for stdbool.h and inttypes.h are available.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1573069 13f79535-47bb-0310-9956-ffa450edef68