v5.34.4

• Fix warn_unused_result warnings produced by gcc/clang #142
• Avoid xmlSAXUserParseFile #140
• Fix compilation with c17 c23 #133
  Most importanty set _POSIX_C_SOURCE to ensure certain calls, fdopen, strerror_r are available.
  C23 now regards bool as keyword, so avoid using bool for function name.
• Allow spaces for auth strings in yaz-client #101
• Fix malformed XML generated from malformed marc #100
• Avoid urbk_safeClone; Use ubrk_clone instead #98