Use default http client

[duhruh]

I think it's useful to use the default client here, it allows us to instrument our own client if need be. This is just the simplest way to accomplish this. Ideally I would like to pass this in via a struct type field, but didn't wanna deal with the refactor overhead of that.

[codecov-io]

Codecov Report

Merging #35 (d006945) into master (9410002) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #35   +/-   ##
=======================================
  Coverage   68.35%   68.35%           
=======================================
  Files           5        5           
  Lines        1163     1163           
=======================================
  Hits          795      795           
  Misses        201      201           
  Partials      167      167           

Impacted Files	Coverage Δ
huego.go	74.54% <100.00%> (ø)

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[amimof]

@duhruh Thanks for this 👏 Looks good to me.

[yunginnanet]

Ideally I would like to pass this in via a struct type field, but didn't wanna deal with the refactor overhead of that.

Good news, I did it for you! #53