Comment header for src/test/regress/regress.c

I thought it might be useful to add a few words at the top
of 'src/test/regress/regress.c' to explain what it does and
to help differentiate it from 'pg_regress.c' and
'pg_regress_main.c'.


Regards

Ian Barwick

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  Ian Barwick                   http://www.2ndQuadrant.com/
  PostgreSQL Development, 24x7 Support, Training & Services