NAT implementation

[JaneCX]

nat

[codecov[bot]]

Codecov Report

Merging #15 into master will decrease coverage by 8.83%. The diff coverage is 10.22%.

@@            Coverage Diff            @@
##           master     #15      +/-   ##
=========================================
- Coverage   66.73%   57.9%   -8.84%     
=========================================
  Files           5       5              
  Lines         475     563      +88     
=========================================
+ Hits          317     326       +9     
- Misses        158     237      +79

Impacted Files	Coverage Δ
src/network.rs	50.92% <10.22%> (-15.05%)	:arrow_down:

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[codecov-io]

Codecov Report

Merging #15 into master will decrease coverage by 7.24%. The diff coverage is 12.32%.

@@            Coverage Diff             @@
##           master      #15      +/-   ##
==========================================
- Coverage   66.73%   59.48%   -7.25%     
==========================================
  Files           5        6       +1     
  Lines         475      548      +73     
==========================================
+ Hits          317      326       +9     
- Misses        158      222      +64

Impacted Files	Coverage Δ
src/main.rs	2.63% <ø> (ø)	:arrow_up:
src/network.rs	65.98% <66.66%> (+0.01%)	:arrow_up:
src/nat.rs	7.46% <7.46%> (ø)

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Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update e16ee70...e2679f1. Read the comment docs.

[changlan]

Travis CI build is failing. Please fix the build error. Thanks!