Add tags to "created by" metadata in the file footer

[asfimport]

Hive has been writing timestamp (without time zone) data incorrectly by converting a timestamp with no time zone to UTC. There is no way to know that Hive definitely wrote the files, so it is difficult to add a recovery mechanism in the object model. Adding a tag for the object model to the "created by" metadata will allow us to detect situations like this in the future.

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

Related issues:

• Release Parquet-mr 1.9.0 (blocks)
• Add metadata field describing the application that wrote the file (is duplicated by)

PRs and other links:

• PR #289

_{Note: This issue was originally created as PARQUET-352. Please see the migration documentation for further details.}

[asfimport]

Ryan Blue / @rdblue:
Implemented a fix that adds getName to the WriteContext that is automatically included in the footer key-value metadata. In future API versions, we can require this to be defined but it is optional now for compatibility.

[asfimport]

Ryan Blue / @rdblue:
Merged #289.