[bug#78033] [PATCH] algol68: rename A68 to A68C and AM_PROG_A68 to AM_PROG_A68C

Jose, Bruno, all - I'd really like to get the automake release out the
door. Can we please come to a final conclusion about the names for the
Algol 68 variables? Does anyone (Paul?) have a problem with going back
to A68/A68FLAGS and leaving out the C? --thanks, karl.