[c-nsp] ASR 9000

[Kevin Graham]

> Runs IOS XR, while the recent ASR 1000 series runs IOS XE?  Consistency 

> would be nice.

...or atleast call this a CRS-2 or something. I'm still crossing my fingers
that there's a master plan for consistency (or alternatively, clear
differentiation) between XR/XE/12.2SX/12.2SR/NX-OS.

> Re-uses the RSP nomenclature, just recently put to bed in the 7500 series.

Nope, 7600 already revived it (RSP720). I don't see reference to line cards,
but the photos look like ES40's, which finally gives some credibility to the
6500/7600 split (where new linecards are shared between ASR9000 and 7600).