Include the listening port number in the server object

[doughamlin]

What kind of change does this PR introduce?
feature

Did you add or update the examples/?
no

Summary
Exposes the listening port number in the server object.
Implements request in #998.

Does this PR introduce a breaking change?
No

[jsf-clabot]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #1053 into master will increase coverage by 0.05%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1053      +/-   ##
==========================================
+ Coverage   72.25%   72.31%   +0.05%     
==========================================
  Files           4        4              
  Lines         465      466       +1     
  Branches      139      139              
==========================================
+ Hits          336      337       +1     
  Misses        129      129

Impacted Files	Coverage Δ
lib/Server.js	79.87% <100%> (+0.06%)	⬆️

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[doughamlin]

I just realized this doesn't fully address the request in #998 because there is no listening event. It is easy enough to extend Server from EventEmitter and emit the listening event when the server starts listening, but I question the need for that when the server object is accessible inside the server.listen callback.

[shellscape]

Much appreciate you taking the time to open a PR 🍻 however #998 seems to me to request automatic port assignment, along with making the random port assigned available for inspection, rather than just exposing the port assigned. I'm not sure you're on the same page as the issue author here.

Check out #1054

[doughamlin]

@shellscape Yeah, I don't know why I thought portfinder was already being used in lib/Server.js and thus all that was needed was exposing the port.

[shellscape]

closing in favor of #1054. thanks again for the PR.

@doughamlin I think portfinder is still needed to check to see if the specified port is in use.