o use predefined macros to test for sys/wait.h, time.h and sys/time.h
o search strcasecmp in libresolv only if strcasecmp and stricmp are not in libc
o use predefined macro AC_SYS_LARGEFILE to determine 64Bit I/O
o determine the alignment of long and double (ALIGNMENT,DOUBLE_ALIGN),
still need to write a test for FB_ALIGN!
o since the define 'VAX' was only used to tell that the byte order is
LITTLE_ENDIAN (it have nothing else to do with the VAX computer family)
it can safely replaced with '!WORDS_BIGENDIAN'.
o check if pointers are 64 bit
o replaced HAS_64BIT_POINTERS with 'SIZEOF_VOID_P == 8'
