Add hierarchy group levels to table_body in tbl_hierarchical()

[edelarua]

What changes are proposed in this pull request?

• Added columns to table_body as returned by tbl_hierarchical() to keep information on all hierarchy levels.

Closes #2070

@ddsjoberg 2 questions:

• What do we want to name these columns? variableXX and variableXX_level? I wasn't sure since we already have a variable column in table_body so I left it as groupXX and groupXX_level for now.
• Do we want to add the innermost level as well even though it should always be represented by variable where applicable?

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[ddsjoberg]

Thank you @edelarua !

What do we want to name these columns? variableXX and variableXX_level? I wasn't sure since we already have a variable column in table_body so I left it as groupXX and groupXX_level for now.

I think that is perfect.

Do we want to add the innermost level as well even though it should always be represented by variable where applicable?

Probably don't need it right? I could go either way

[ddsjoberg]

this is great, i love it! Can we make one small change? Can you move the grouping columns to after the row_type column? I prefer keeping all the hidden column grouped together in the beginning of the data frame.

[edelarua]

this is great, i love it! Can we make one small change? Can you move the grouping columns to after the row_type column? I prefer keeping all the hidden column grouped together in the beginning of the data frame.

Done!

[ddsjoberg]

Lovely, thank you @edelarua !