TPAC: Propagate CGI params via mkurl()

TPAC: Propagate CGI params via mkurl()

Fix many instances where params such as "loc" are dropped during a
normal workflow, resulting in unexpected changes to the user's chosen
search scope. mkurl() preserves the existing CGI params by default
and passes them on to the created URL; for now we err on the side of
caution (preserving all params) rather than filtering any out. Manual
testing suggests this does not introduce any problems, and resolves
many.

Signed-off-by: Dan Scott <dan@coffeecode.net>
Signed-off-by: Bill Erickson <berick@esilibrary.com>