tests: enable snmp tests

Enabled snmp tests against snmpd on localhost. It was installed already
in the travis file, we just need to enable the tests by setting the
parameters in the answers file.

Signed-off-by: Sven Nierlein <sven@nierlein.de>

plugins/t/NPTest.cache.travis

@@ -11,7 +11,7 @@
   'NP_HOST_NONRESPONSIVE' => '10.0.0.1',
   'NP_HOST_RESPONSIVE' => 'localhost',
   'NP_HOST_SMB' => '',
-  'NP_HOST_SNMP' => '',
+  'NP_HOST_SNMP' => 'localhost',
   'NP_HOST_TCP_FTP' => '',
   'NP_HOST_TCP_HPJD' => '',
   'NP_HOST_HPJD_PORT_INVALID' => '161',
@@ -39,7 +39,7 @@
   'NP_SMB_SHARE_SPC' => '',
   'NP_SMB_VALID_USER' => '',
   'NP_SMB_VALID_USER_PASS' => '',
-  'NP_SNMP_COMMUNITY' => '',
+  'NP_SNMP_COMMUNITY' => 'public',
   'NP_SSH_CONFIGFILE' => '~/.ssh/config',
   'NP_SSH_HOST' => 'localhost',
   'NP_SSH_IDENTITY' => '~/.ssh/id_dsa',