exceptions: add master switch config option

exceptions: add master switch config option

This allows all traffic Exception Policies to be set from one
configuration point. All exception policy options are available in IPS
mode. Bypass, pass and auto (disabled) are also available in iDS mode

Exception Policies set up individually will overwrite this setup for the
given traffic exception.

Task #5219

(cherry picked from commit 0d9289014bd8f65c7100e7173f24f5c5ff9de0ac)