Improve management of non plugin related dependencies

[pmouawad]

Today when you want to have a dependency of your test like ActiveMQ added to lib, you have no easy OOTB way.

It is possible in 1.X versions but not possible without some hacks in 2.x up to 2.5.1 version.

FI : @Ardesco

[Ardesco]

Looks like we potentially started pushing files to the wrong directory in 2.x

These lines look suspicious:

https://github.com/jmeter-maven-plugin/jmeter-maven-plugin/blob/master/src/main/java/com/lazerycode/jmeter/mojo/ConfigureJMeterMojo.java#L307

https://github.com/jmeter-maven-plugin/jmeter-maven-plugin/blob/master/src/main/java/com/lazerycode/jmeter/mojo/ConfigureJMeterMojo.java#L467

[pmouawad]

Hi @Ardesco ,
IMU, jmeterExtensions was for plugin as per this doc:
https://github.com/jmeter-maven-plugin/jmeter-maven-plugin/wiki/Adding-additional-libraries-to-the-classpath

If it's the case then code looks good to me.

[Ardesco]

In that case phew! It's just missing functionality, not something I broke :)