check_ntp_peer: do not use uninitialized results for max state

s/t/jresult are not initialized if there is no corresponding threshold
supplied. So we shouldn't use them for calculating our result.

Signed-off-by: Sven Nierlein <sven@nierlein.de>
tests: check_disk_smb may exit with critical for unresponsive hosts too

Unknown (ex. debian 7)
%> ./check_disk_smb -H 1.1.1.1 -s np_foobar -vvv
/usr/bin/smbclient //1.1.1.1/np_foobar -U guest% -c du
No Answer from Client

Critical (ex. debian 8)
%> ./check_disk_smb -H 1.1.1.1 -s np_foobar -vvv
/usr/bin/smbclient //1.1.1.1/np_foobar -U guest% -c du
Connection to 1.1.1.1 failed
CRITICAL

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>
check_dns: unified check output

this also allows us to make tests against "critical" in the output.

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>
tests: get current directory the perl way

instead of hoping to have it in the environment. This at
least broke tests on solaris.

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>
tests: negate test fails when not run from plugins folder

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>
tests: skip extented snmp tests if snmpd has no perl support

solaris snmpd has no perl support by default, so this test will fail.

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>
check_by_ssh: added --hostname support

just like the guidelines and the help already suggests.

Signed-off-by: Sven Nierlein <sven@nierlein.de>
Add check_ifstatus option to ignore interfaces by name

Ignoring by index is not always an option, as the index can change on
chassis switches as blade configurations change.
NEWS: Mention new check_ifstatus option