Add support for additional Docker port bindings

[treydock]

No description provided.

[codecov]

Codecov Report

Merging #54 (9c0d804) into master (b47d868) will increase coverage by 0.25%.
The diff coverage is 100.00%.

❗ Current head 9c0d804 differs from pull request most recent head 1cfe5ce. Consider uploading reports for the commit 1cfe5ce to get more accurate results

@@            Coverage Diff             @@
##           master      #54      +/-   ##
==========================================
+ Coverage   84.82%   85.08%   +0.25%     
==========================================
  Files           1        1              
  Lines         290      295       +5     
==========================================
+ Hits          246      251       +5     
  Misses         44       44              

Impacted Files	Coverage Δ
lib/beaker/hypervisor/docker.rb	85.08% <100.00%> (+0.25%)	⬆️

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[bastelfreak]

looks sane to me. But would be nice if @trevor-vaughan could take a look at well.

[trevor-vaughan]

Sorry that this took so long to check! This looks good to me.