ipsec: add insecure option for format of SA

If specified, shows keys, otherwise redacts. This change sets this flag
in the existing CLI code (thus maintaining the old behavior). The use
case for not specifying the insecure flag (and thus redacting the keys
from the show output) is for log messages.

Type: feature
Signed-off-by: Christian E. Hopps <chopps@chopps.org>
Change-Id: I8c0ab6a9a8aba7c687a2559fa1a23fac9d0aa111