Offer project templates for use with the maven-archetype-plugin

[ctrueden]

It would be nice to be able to initialize a new Maven project for a new ImageJ2 command via:

mvn archetype:generate -DarchetypeArtifactId=imagej2-command

Follow https://maven.apache.org/archetype/maven-archetype-plugin/advanced-usage.html to provide that.

We probably also need to provide an archetype catalog: https://maven.apache.org/archetype/maven-archetype-plugin/specification/archetype-catalog.html

Migrated-From: http://trac.imagej.net/ticket/1924

[ctrueden]

@dscho's first attempt: https://github.com/imagej/minimal-ij1-plugin/tree/archetype

[dscho]

I worked a bit more on this, but have to concentrate on other projects now. @ctrueden feel free to give this project to @apal4 or @hinerm, or to do it yourself.

[ctrueden]

Thanks @dscho. Assigning to myself so I don't forget about it, but it will probably be quite some time before we get back to it.