mydumper: add select filter

[codecov[bot]]

Codecov Report

Merging #24 into master will decrease coverage by 0.54%. The diff coverage is 80%.

@@            Coverage Diff             @@
##           master      #24      +/-   ##
==========================================
- Coverage   95.15%   94.61%   -0.55%     
==========================================
  Files           5        5              
  Lines         454      464      +10     
==========================================
+ Hits          432      439       +7     
- Misses         11       12       +1     
- Partials       11       13       +2

Impacted Files	Coverage Δ
src/common/common.go	86.36% <ø> (ø)	:arrow_up:
src/common/dumper.go	94.07% <80%> (-1.93%)	:arrow_down:

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[geshan]

+1 👍