Read one line from stdin.  Break it into keyword value pairs.  Print
them out.  Pairs are separated in standard CGI fashion, by an
ampersand (&).  Keys and values are separated by equals (=).  Spaces
are replaced by plus (+).  Other strange characters are replaced by
their hexidecimal equivalent (%xx).

Each keyword is a product name, and each value is a quantity.  Create
an HTML table listing the products and quantities.  Your formatting
must match GradeBot's, of course.  (No tabs are used by GradeBot.)

Hint: The following s/// substitution will be helpful for dealing with
those strange characters.  s/%([\da-f][\da-f])/pack("C",hex($1))/eig;