Location for user dependencies +Ivy Dependency downloader

[Freshwood]

We had some problems with the nexus repository in conjunction with the Apache Toree incubator.

The coursier dependency manager is incompatible with Nexus repository manager. We could not use the magics %AddJar + %AddDeps in a normal way.

With the Ivy dependency manager we had no problems.

Changes:

We introduced a new setting 'ivy-settings' where an user can link an ivy-configuration file Maybe it is useful for other people, too.

[lresende]

@Freshwood Could you please describe a little bit more on the changes related to the location for user dependencies.