Add ip tunnel instructions readme

[aljones15]

1. Adds a Table of Contents to the README more inline with a standard README
2. Adds a Usage section to the README
3. Adds a section in configuration on IP Tunnels

[codecov-commenter]

Codecov Report

Merging #33 (adec0ae) into main (447d07c) will not change coverage.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #33   +/-   ##
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  Coverage   92.20%   92.20%           
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  Files           2        2           
  Lines         231      231           
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  Hits          213      213           
  Misses         18       18           

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[mattcollier]

Binding a service to 0.0.0.0 means that your service will listen on all it's network interfaces.

https://stackoverflow.com/questions/71681234/what-does-bind-0-0-0-0port-mean-in-node-command-line#:~:text=Binding%20a%20service%20to%200.0,inside%20your%20local%20network%20(192.168.

[aljones15]

0.0.0.0 means a lot of different things I've found so thanks for the clarification. Made the change here: f9694da

[dlongley]

@mattcollier, it seems a little odd to me that this isn't using bindAddr here but domain.