Agent appearance not reset in evaluation.py

[philipjhj]

In evaluation.py (75d0bfb) the agent's appearance is not reset.

Command obs = env.reset() is missing suitable agent_type as input, i.e obs = env.reset(agent_type)

[petrosgk]

This also leads to the color of the challenge agent's helmet not changing depending on whether it's Random or Focused..

[philipjhj]

Exactly, see #40