Bug 8492 [ENH] Restrict OpacSuppression to IP adresses outside of an IP range

Bug 8492 [ENH] Restrict OpacSuppression to IP adresses outside of an IP range

This enhancement extends the OpacSuppression feature with an optional IP address range within which results are _not_ suppressed.

To test

* turn on OpacSuppression (Administration->System preferences->Cataloging) and enter an IP address range in the OpacSuppressionByIPRange field.
* set at least one bibliographic record to suppress=1 (enter '1' in 942$n)
* fully reindex your data
* do an OPAC search that should bring up your suppressed record
* try with IP ranges that match your IP and ranges that don't

Signed-off-by: Marc Veron <veron@veron.ch>
Tested following the scenario above. Works as expected.