Allow special email address 'guest'.

Used for anonymous login in policy-web
Fixed check for redundant rules with global permit

No longer allow ports in global permit.
Fixed comment.
Added tests for global:permit.
Ignore bridged interface in check for dupl. routes
Fixed 'Use of uninitialized value' with hidden NAT
Check useless overlaps if check_redundant_rules=0

We now get warnings about useless overlaps, even if
check_redundant_rules=0 and/or check_duplicate_rules=0.
Fixed comment.
Don't check unenforceable on disabled service.
Fixed wrong warn/err print from cb6af847d3
Fixed $Netspoc::file to $Netspoc::current_file
Remove duplicate elements from network|any:[...]

Ignore duplicate networks and aggregates in automatic group resulting
from different interfaces connected to the same object.
Mark secondary ip address as 'secondary' for NXOS