More fixes for .m2 cache

There were a few typos in the cache
specification which may be related,
but likely the overall problem that
we're seeing is:

  https://issues.apache.org/jira/browse/IVY-1088
Hack: isable pom usage for downloaded resources

I have no idea why this is necessary, but with poms
activated, `ivy:retrieve` doesn't symlink any jars
under target/libs despite the fact that the files
**are** downloading under `~/.m2`. This is certainly
suboptimal and more complex requirements will likely
fail if we ignore their dependencies, but this does
allow the metrics jar to be available.