[tor-relays] OrNetStats: Operator Level Graphs added

[nusenu]

> Maybe nitpicking but IMO It is irritating, that the 0% value (zero)
> of the left y-axis doesn't match the 0 GBit/s at the right y-axis
> (per default).

I find it actually useful to have distinct scaling and offsets
for the two y axis, because this way the available space is used 
more efficiently, no?
After learning that these are not starting at 0, things should
be clear.

What doesn't make sense for me: negative ranges, which I'll
try to address soon.

thanks for your input,
nusenu