Different created_by field values for application and library

There seems to be a discrepancy in the Parquet format created_by field regarding how it should be filled out. The parquet-mr library uses this value to enable/disable features based on the parquet-mr version [here](https://github.com/apache/parquet-mr/blob/5f403501e9de05b6aa48f028191b4e78bb97fb12/parquet-column/src/main/java/org/apache/parquet/CorruptDeltaByteArrays.java#L64-L68). Meanwhile, users are encouraged to make use of the application version [here](https://www.javadoc.io/doc/org.apache.parquet/parquet-format/latest/org/apache/parquet/format/FileMetaData.html). It seems like there are multiple fields needed for an application and library version. 

**Reporter**: [Joshua Howard](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=joshthoward@gmail.com)

_{**Note**: *This issue was originally created as [PARQUET-2088](https://issues.apache.org/jira/browse/PARQUET-2088). Please see the [migration documentation](https://issues.apache.org/jira/browse/PARQUET-2502) for further details.*}

Start with the linked parquet-mr CorruptDeltaByteArrays.java logic and the FileMetaData.java documentation to understand how created_by is currently interpreted. Determine the required separation between application and library versions; done requires an agreed format/API direction and the corresponding implementation or documentation scope to be defined.

Written by the indexing model from the issue text.