Add support for filters

[codecov-commenter]

Codecov Report

Merging #144 (7131f66) into master (7745e19) will increase coverage by 0.76%. The diff coverage is 96.72%.

@@            Coverage Diff             @@
##           master     #144      +/-   ##
==========================================
+ Coverage   78.77%   79.53%   +0.76%     
==========================================
  Files          30       31       +1     
  Lines        1366     1427      +61     
==========================================
+ Hits         1076     1135      +59     
- Misses        200      201       +1     
- Partials       90       91       +1     

Impacted Files	Coverage Δ
filters.go	96.72% <96.72%> (ø)

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[mattn]

Thank you