[Devmon] counter-wrap issues

[Schwimmer, E. E *H. <EE...@hs...>]

Looks like there is some counter-wrap issues in the DELTA
transform code.  I'm fixing it now.

However, on very high speed interfaces that are only polled
in-frequently, I cant garuanteed the accuracy of the counters
(as your counter could wrap an arbitrary number of times
between polling cycles, and there's no way to find out).=20
I'll see about working 64-bit counters into this routine.

-Eric Schwimmer
Network Engineer
UVA HSCS Network Engineering=20