[c-nsp] sup2T software & release notes have hit

[Phil Mayers]

...and the first thing that stands out in the release notes:

"""
These features are not supported in Release 12.2(50)SY:

•Per-VLAN Spanning Tree (PVST) mode

Note Release 12.2(50)SY supports these spanning tree protocols:
—Rapid Spanning Tree Protocol (RSTP) is enabled by default;
—Multiple Spanning Tree Protocol (MSTP) is supported.
"""

I sincerely hope that's a "next release" feature... Anyone know anything 
about this? Seems like an amazing thing to miss out, given the 
limitations of MST (only one MST process per switch)