PARQUET-2488: Use term row consistently in parquet.thrift

[alamb]

As discussed on the mailing list (thread link) , parquet.thrift uses the terms record and row to mean the same thing, which could cause confusion

The consensus on the mailing list was to use the term "row".

This PR proposes changing parquet.thrift so it only uses the term 'row'

Jira

• My PR addresses the following Parquet Jira issues and references them in the PR title. For example, "PARQUET-1234: My Parquet PR"
  • https://issues.apache.org/jira/browse/PARQUET-2488
  • In case you are adding a dependency, check if the license complies with the ASF 3rd Party License Policy.

Commits

• My commits all reference Jira issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

• In case of new functionality, my PR adds documentation that describes how to use it.
  • All the public functions and the classes in the PR contain Javadoc that explain what it does

[alamb]

Thank you @julienledem and @emkornfield