MUCC: Implement the open_tmp_file() RA callback so "put" doesn't crash against http:// URLs.
MUCC: Implement the open_tmp_file() RA callback so "put" doesn't crash
against http:// URLs.

* contrib/client-side/mucc.c
  (open_tmp_file): New.
  (ra_callbacks): Set RA callback vtable member 'open_tmp_file' to
    our new open_tmp_file() function.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion