onCell add row index

[yoyo837]

As title.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@ec5ce64). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #222   +/-   ##
=========================================
  Coverage          ?   93.58%           
=========================================
  Files             ?       17           
  Lines             ?      748           
  Branches          ?      196           
=========================================
  Hits              ?      700           
  Misses            ?       40           
  Partials          ?        8

Impacted Files	Coverage Δ
src/TableCell.js	97.82% <100%> (ø)

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[yesmeck]

What's the scenario do you need the index? index is not reliable.

[yoyo837]

For handle different logic every cell.