Restore ParquetInputSplit methods from 1.5.0

[asfimport]

Need to add back API methods on ParquetInputSplit that were present in 1.5.0

Reporter: Ryan Blue / @rdblue
Assignee: Ryan Blue / @rdblue

Related issues:

• Release parquet-mr 1.6.0 (blocks)

PRs and other links:

• PR #159

_{Note: This issue was originally created as PARQUET-234. Please see the migration documentation for further details.}

[asfimport]

Ryan Blue / @rdblue:
Fixed in PR #59.

[asfimport]

Ryan Blue / @rdblue:
Merged #159.