Renamed chpl_glob to chpl_study_glob to avoid name conflict

Continuing my game of glob whack-a-mole, when adding our
new runtime chpl_glob() routine yesterday, it failed to occur
to me that it would conflict in name with this routine that Tim
used in his test when he was doing an initial prototype of
glob().  I've had a long-term TODO to rewrite Tim's test to
use filerator routines (and move both sets of tests into the
test/modules/standard hierarchy), but for now am just renaming
his chpl_glob() to silence last night's failures.