WIP: Add Cloudwatch graph (Metrics) to grabana

[botanikanet]

https://grafana.com/docs/grafana/latest/datasources/aws-cloudwatch/query-editor/#create-a-metric-search-query

[codecov]

Codecov Report

Attention: 10 lines in your changes are missing coverage. Please review.

Comparison is base (fec9fee) 89.71% compared to head (6f0a853) 89.65%.
Report is 2 commits behind head on master.

❗ Current head 6f0a853 differs from pull request most recent head 2c94db9. Consider uploading reports for the commit 2c94db9 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #252      +/-   ##
==========================================
- Coverage   89.71%   89.65%   -0.06%     
==========================================
  Files          92       93       +1     
  Lines        7036     7092      +56     
==========================================
+ Hits         6312     6358      +46     
- Misses        572      581       +9     
- Partials      152      153       +1     

Files	Coverage Δ
graph/graph.go	98.50% <100.00%> (+0.09%)	⬆️
target/cloudwatch/cloudwatch.go	100.00% <100.00%> (ø)
decoder/graph.go	60.45% <0.00%> (-1.05%)	⬇️
decoder/target.go	96.15% <0.00%> (-3.35%)	⬇️