_id --> _uid
cleanup, pep8, comments
frontend expectes `state` to be a string/None atm
nodes with type "Native" do not exist (anymore)
consolidate step_world/step_nodenet
always deliver `current_step`
gate_id --> gate_name
step --> current_step frontend
Merge pull request #50 from Doik/redundancy_hunt

Merging Doik's cleanup commits.