Add maven wrapper to simplify pipelines

[dashaun]

I read the README, checked out the repository, and I assumed the maven wrapper would be included.

https://github.com/takari/maven-wrapper

I don't have mvn installed.

The wrapper helps insure that users are using the same version.

I noticed issue #24 was around adding maven features, using the wrapper will also help there. It removes the need to document which minimum version of mvn to install.