[c-nsp] IOSXR upgrade procedures Was: 6500, 7600 or ASR

[Adam Vitkovsky]

Regarding the ISSU I heard there's a plan to run something like two codes on
the LC asics so that one can be upgraded while the other sill performs the
forwarding duties. 

As far as the upgrade process goes. Yes it's a bit more complex than simple
next->next->next->,  but once you've done 13 in a row it becomes a routine. 

adam