Bug 8910 - silent warnings triggered in about.pl

Bug 8910 - silent warnings triggered in about.pl

In order to detect the apache version, there are multiple
commands used. These may not all exist, which triggers error log
entries. By simply adding " 2> /dev/null", the errors are no
longer generated.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Liz Rea - Catalyst <liz@catalyst.net.nz>