Merge pull request #230 in CASA/casa6 from CAS-13149 to master
* commit 'b28b6de0b1af82c34edd6a80cd84faee0acb5e23':
trap overflow exceptions in CASA 5 (CAS-13149)
use ssize_t for shape/size (CAS-13149)
remove variant LONG/LONGVEC from variant (CAS-13149)
fix integer conversion (CAS-13149)
switch the casa binding's basic integral type from int to long (CAS-13149)