SPT: Pick up ACPGD2.DAT if it exists

SPT can be made to run reading ACPGD2.DAT instead of PGDX3.DAT.  This is
useful when running an accretion disk system with black body
approximation.
SPT: Added output mesg for VLIGHT<=0
SPT: prevent success mesg on errors

SPT was erroneously printing "SUCCESSFULLY COMPLETED" when in fact the
program terminated due to an error reading observation light curve.
This patch adds some logic necessary to suppress that message.
Test5 Fixes

Some missing files in Test5/ were added.

Removed cp commands in script1 that pertain to more than one color.
Test5 is configured for only one color.
make defaults: added init-zero all local variables

Problems were found with PGB on Intex/OS X and ACPGF6 for Test4.