Support In-situ Operation Administration and Maintenance (IOAM)

[jingfeihu]

1.support CMCC IOAM over ipv4/ipv6 + tcp/udp/vxlan 2.add CMCC IOAM unit tests

[codecov[bot]]

Codecov Report

Merging #4232 (f93e029) into master (d71014a) will decrease coverage by 32.65%. Report is 5 commits behind head on master. The diff coverage is 46.15%.

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #4232       +/-   ##
===========================================
- Coverage   81.77%   49.12%   -32.65%     
===========================================
  Files         331      332        +1     
  Lines       76721    76752       +31     
===========================================
- Hits        62736    37703    -25033     
- Misses      13985    39049    +25064     

Files	Coverage Δ
scapy/contrib/ioam.py	100.00% <100.00%> (ø)
scapy/layers/inet6.py	41.22% <54.54%> (-47.33%)	:arrow_down:
scapy/layers/inet.py	24.09% <0.00%> (-46.53%)	:arrow_down:

... and 232 files with indirect coverage changes

[guedou]

@jingfeihu it looks like some tests are failing. I converted your PR to a draft. Feel free to modify it when it is ready.