normalize path part of uri:classloader: paths
allow uri: protocol pathes in Gem.path or GEM_PATH
allow to change directory into the uri:classloader:// space
adds test which assembles a runnable.jar and uses CWD inside the jar

this example uses Gemfile for the gem dependencies, Jarfile for jar dependencies,
a Rakefile setting up bundler, a rspec test verifying that all gems, jars and the
CWD are all inside the jar