added support for ControlNodes aka non-system, non-patcher nodes

[fde31]

closes #70

[x37v]

one note @fde31
this doesn't dynamically update when you add a new jack client, you can test this by doing this:

• start the web UI and target your pi
• ssh to your pi
• run jack_midi_dump
  • you may have to sudo apt-get install jack-tools before

you should see midi-monitor now in the graph but you don't until you reload the page

[fde31]

ok should be addressed now. Want to test it once more @x37v ?

[x37v]

working great!