fix default logging levels to NOTICE, not DEBUG

Tweak unit test binaries to still used DEBUG loglevels, so that their expected
outputs remain unchanged (and nicely verbose).

Adjust test_nodes.vty, now expecting the 'notice' log levels upon
'show running-config'.

Change-Id: Ic061e61c9625b49cef8bc2a2c0b936e262c22268
5 files changed