AddIPv4 returns change

[ddymko]

Description

AddIPv4 will now return the IP address that was just created.

Related Issues

Closes #76

Checklist:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Have you linted your code locally prior to submission?
• Have you successfully ran tests with your changes locally?

[codecov]

Codecov Report

Merging #77 into master will increase coverage by 0.02%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master      #77      +/-   ##
==========================================
+ Coverage   71.98%   72.00%   +0.02%     
==========================================
  Files          24       24              
  Lines        2702     2704       +2     
==========================================
+ Hits         1945     1947       +2     
  Misses        381      381              
  Partials      376      376              

Impacted Files	Coverage Δ
server.go	71.29% <66.66%> (+0.08%)	⬆️

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