Github user vrozov commented on the issue:
https://github.com/apache/drill/pull/1207
-1 on removing apache-rat maven plugin. It is an Apache plugin to invoke
"Release Audit Tool". More plugins can be added to check license headers if
they do a better job in addition to apache-rat.
Both apache-rat and any other license verification plugins can be disabled
by default (this will allow to run `mvn -T 2C clean install` if necessary) and
only enabled in Travis CI.---
