Bug 4510 Script processes single supplier not an array

Bug 4510 Script processes single supplier not an array

Script was written as though it had an array rather than
a single supplier. Replaced the excess punctuation with a single
supplier variable

replaced the C-style currency loop with a simpler perl-style one
we only need 1 loop not multiples
Changed variable name $GST to $tax_rate it's not magical and not a constant
and we all know what tax is
Fetch Contract data once rather than twice from two different modules
Correct size of discount data on display

Signed-off-by: Galen Charlton <gmcharlt@gmail.com>