- Added missing HAVE_SYS_TIMES_H, HAVE_SYS_TIME_H, HAVE_TIME_H,
   HAVE_TIME and HAVE_TIMES
 - Removed most #if constructs, keep logic in "configure.cmake"
 - Use space after # if inside #if, for consistency

configure.cmake
 - Added MY_CHECK_TYPE_SIZE function that sets both SIZEOF_* and HAVE_*
 - If "sys/stream.h" exists, include it before "sys/ptem.h" in test
 - Set VOID_SIGHANDLER if RETSIGTYPE is set to "void"