Wire license-maven-plugin + commit into release builds

[badgerwithagun]

Our licence mastheads have a tendency to go missing or out of date. I've had a lot of success with (one of the) Maven plugins for this purpose:

        <plugin>
          <groupId>com.mycila</groupId>
          <artifactId>license-maven-plugin</artifactId>
          <version>3.0</version>
          <configuration>
            <header>etc/HEADER</header>
            <includes>
              <include>**/*.java</include>
              <include>**/*.js</include>
              <include>src</include>
            </includes>
            <excludes>
              <exclude>src/test/resources/**</exclude>
              <exclude>src/main/resources/**</exclude>
            </excludes>
          </configuration>
        </plugin>

I like the simplicity of this one - it just inserts the content of a defined HEADER file at the top of every file in a language-appropriate way (it handles the correct commenting style for the file type).

Example of a HEADER file:

Spline Reticulator
Copyright © 2018-2019 Horace

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

The only complication is where to wire it in. What I do is to run it using a "release" profile in a format-only build, then commit+push, then run the main build, as three separate steps in a release pipeline. This means it only kicks in when a release is performed.