Bug 27824: Trim column headers

Bug 27824: Trim column headers

To support additional spaces.

Using the system for defining a column name placeholder (Bug 23390), if
there is a space inside the column name placeholder it won't work. The
SQL example in Bug 5697:

SELECT
i.itemnumber,
i.itemnumber as Exemplarnummber,
[[i.itemnumber| itemnumber for batch]],
CONCAT('<a
href=\"/cgi-bin/koha/cataloguing/additem.pl?op=edititem&biblionumber=',
i.biblionumber, '&itemnumber=', i.itemnumber, '#edititem', '\">',
i.itemnumber, '</a>' ) AS "itemnumber as edit link"
FROM items i

"[[i.itemnumber| itemnumber for batch]]" has a space before "itemnumber
for batch." With that space removed it works as expected.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>