Bug 22824: Add warning to the about page

Bug 22824: Add warning to the about page

Just in case, add a warning to the about page.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
JD amended patch: there was a "bad space" between "warnNoActiveCurrency"

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>