More progress with JRubyArt (Alternative ruby-processing implementation)

Now JRubyArt can run with a post-install vendored jruby-complete (this is is unfortunately still required for some sketches owing to a difference in permissions ask @headius).

Comparison

ruby-processing	JRubyArt
rp5 setup install	k9 setup install
rp5 --nojruby run sketch.rb	k9 run sketch.rb
rp5 run sketch.rb	jruby sketch.rb

NB: Regular ruby-processing can be made to always run with vendored jruby-complete in ~/.rp5rc config file, but default is to use an installed jruby. MRI ruby can be used start sketches with run mode, but jruby is used to actually run the sketches.