[Network] improve error logging

[synzhu]

Let's print out the errors encountered so far.

[codecov-commenter]

Codecov Report

Merging #1345 (9523d59) into master (28a6922) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1345   +/-   ##
=======================================
  Coverage   56.25%   56.25%           
=======================================
  Files         500      500           
  Lines       31162    31162           
=======================================
  Hits        17531    17531           
  Misses      11262    11262           
  Partials     2369     2369           

Flag	Coverage Δ
unittests	56.25% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
network/p2p/libp2pNode.go	66.56% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 28a6922...9523d59. Read the comment docs.

[huitseeker]

👍

[synzhu]

bors merge

[bors]

Build succeeded:

• Integration Tests (1.15)
• Integration Tests (1.16)
• Lint
• Unit Tests (1.15)
• Unit Tests (1.16)