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PARQUET-1689: [C++] Stream API: Allow for columns/rows to be skipped when reading

Add methods to the StreamReader class to allow for columns and rows of
data to be skipped.

Also add helper methods for finding out:
- total number of columns
- total number of rows
- current row
- current column

Closes #5797 from gawain-bolton/PARQUET-1689_stream_reader_column_row_skipping and squashes the following commits:

47ad8eb8c <gawain.bolton> Updates after second review by emkornfield on 2019-11-14
5ec4ccab9 <gawain.bolton> PARQUET-1689: Stream API: Allow for columns/rows to be skipped when reading

Authored-by: gawain.bolton <gawain.bolton@cfm.fr>
Signed-off-by: Uwe L. Korn <uwe.korn@quantco.com>