Add --tables option to Tax-Calculator CLI

[martinholmer]

This pull request adds a simple distributional table as an CLI output option: total tax liabilities are shown for each expanded-income decile.

[codecov-io]

Codecov Report

Merging #1258 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1258      +/-   ##
==========================================
+ Coverage   99.67%   99.67%   +<.01%     
==========================================
  Files          38       38              
  Lines        2749     2785      +36     
==========================================
+ Hits         2740     2776      +36     
  Misses          9        9

Impacted Files	Coverage Δ
taxcalc/calculate.py	100% <ø> (ø)	⬆️
taxcalc/behavior.py	100% <100%> (ø)	⬆️
taxcalc/utils.py	99.3% <100%> (ø)	⬆️
taxcalc/taxcalcio.py	100% <100%> (ø)	⬆️

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