Restore the ability to compile with g++. Thanks to
Arnold Robbins.

Matchop dereference after free problem fix when the first
argument is a function call. Thanks to Oguz Ismail Uysal.
Fix inconsistent handling of --csv and FS set in the
command line. Thanks to Wilbert van der Poel.
Casting changes to int for is* functions.

Fix exit status of system on MacOS. Update to REGRESS.
Thanks to Arnold Robbins.
Fix inconsistent handling of -F and --csv, and loss of csv
mode when FS is set.