Command Line: Add options to specify Maven repository

[smarkwal]

Problem

As of today, JarHC only works with Maven Central. The URL to the Maven repository is hard-coded. Users of alternative Maven repositories cannot use JarHC to look up and download artifacts from them.

Goal

Add additional command line options to specify connection details to an alternative Maven repository. Minimum requirement is to be able to specify a repository URL. In addition, it may be possible to provide username and password for a repository which requires authentication.