Request to apply cutting row

[chiendh]

Remove redundant Row class, replace with GSRow struct Remove unnecessary source code of Row class

[knonomura]

That's great ! Thank you very much for your PR. I will check it.

[knonomura]

Row data's put/get process becomes simpler.

Before:

• It handles GSRow object for C Client via an instance of Row class on C++ layer.

After:

• It handles directly GSRow object.
• Row class becomes unnecessary.

I will merge your PR.