[c-nsp] IOS: catch 22 when enabling new bgp neighbors

[Adam Atkinson]

isn't "no bgp default ipv4-unicast" the solution?

from 
http://www.cisco.com/c/en/us/td/docs/ios/iproute_bgp/command/reference/irg_book/irg_bgp1.html#wp1113664

IPv4 address family routing information is advertised by default for 
each BGP routing session configured with the neighbor remote-as command, 
unless you first configure the no bgp default ipv4-unicast command 
before configuring the neighbor remote-as command.