Phs/clean house

The gem needs ruby 1.9.2 and platform java.

Prefer require_relative except in the gemspec itself.

Add pkg to the clean path.

Finally, merge log4j helper with hbase helper, overhaul class loading.

This appears to fix both helpers.  log4j apparently was suffering from
a load order problem, while the hbase jar loading was plain wrong.

The hbase classloading issues were being masked by our test_classpath
file generated from maven.  In fact, with the hbase helper working,
test_classpath is now unnecessary.  It has been removed.

You might notice we don't explicitly test that the hbase jars appear
in $LOADED_FEATURES after load!ing.  Turns out testing that robustly
is a lot harder than it looks.  Compound this with the fact that
travis appears to be doing something fishy with zookeeper jar
symlinks.  Anyway, we satisfy ourselves with loading a few HBase
classes in the test.