configure finds mtx also at /usr/sbin/mtx

some distribution store mtx under /usr/sbin/mtx.
As configure runs as normal user, this path is not set.
This patch let configure also look at sbin paths.

fixes #101: variable MTX is not defined

Signed-off-by: Marco van Wieringen <marco.van.wieringen@bareos.com>
added check for mtx program

Signed-off-by: Marco van Wieringen <marco.van.wieringen@bareos.com>
Rebuild configure.
test -e is not portable.

-e file   True if file exists. (Not available in sh.)
adapted configure to debian configure (bat, tray-monitor)

Signed-off-by: Marco van Wieringen <marco.van.wieringen@bareos.com>
Try using mysql_config if its available.

As there are different versions of mysql_config depending on the version
we test to see what works. This seems to be mostly ok for the current
platforms we build on but we hope for a somewhat stable ABI of the
mysql_config program in the future. This should hopefully save us from
needing to do lots of maintenance on configure for the exotic
distributions out there who put libs in the most exotic places.
Rebuild configure.
bugfix
Merge remote-tracking branch 'upstream/master' into joergs/mvw-users