Add es_ingest_pipeline as an option in constructor.

[onnheimm]

Suggestion for implementing #49.

[codecov-io]

Codecov Report

Merging #50 into master will increase coverage by 0.84%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #50      +/-   ##
==========================================
+ Coverage      83%   83.85%   +0.84%     
==========================================
  Files           2        2              
  Lines         153      161       +8     
  Branches       20       21       +1     
==========================================
+ Hits          127      135       +8     
  Misses         22       22              
  Partials        4        4

Impacted Files	Coverage Δ
cmreslogging/handlers.py	83.11% <100%> (+0.92%)	⬆️

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