[Proposal] Use namedtuples in SndRcvList()

[guedou]

While teaching Scapy, I realized that it is difficult to understand which indices to use to iterate a response of type SndRcvList().

For example, to display the first answer, a user must do:

>>> r, u = sr(IP(dst="8.8.8.8") / ICMP())
>>> r[0][1]

Beginners might do the following, which is more complex to understand:

>>> r = sr(IP(dst="8.8.8.8") / ICMP())
>>> r[0][0][1]

Using a namedtuple instead of a tuple in SndRcvList(), it is possible to simplify the access to the answer with .answer while maintaining [1] for backward compatibility:

>>> r, u = sr(IP(dst="8.8.8.8") / ICMP()
>>> r[0].answer == r[0][1]

Do you think that this feature is interesting?

[gpotter2]

This sounds super reasonable, LGTM.