pgbouncer - pgbouncer: More descriptive usage screen.

Log Message:
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More descriptive usage screen.

Slightly modified from patch by Jacob Coby.

Modified Files:
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pgbouncer/src:
main.c (r1.38 -> r1.39)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbouncer/pgbouncer/src/main.c.diff?r1=1.38&r2=1.39)