Set up a new webots world for the simulation of a homeo-controlled Braitenberg type 1-like  vehicle

The khepera-like robot has one light sensor and one motor
(the two motors always act in unison, with the same speed values)

The world is flat, empty and with two sources of light
Setup first real robotic experiment with Homeo: a Braitenberg-like type 1 vehicle with only one Homeo unit

It is the simplest possible rendering of the Homeo setup:

- one real HomeoUnit controls the motor of the type-1 vehicle

- one HomeoUnitInput (not a real unit, just an interface to the robotic sensor)
   reads the value from the (only) light sensor

- the motor-controlling Homeo unit reads the light value from the sensor
  (through the HomeoUnitInput)

The simulation uses the standard Homeo GUI for starting/stopping/controlling and visualizing the experiment.

The simulation setup works:
- proper communication between webots and
- proper visualization of relevant parameters
- proper control of the robot from the homeostat

However, the experiment itself fails: the robot keeps going straight without ever stopping.
Minor fixes to the Braitenberg tests with Webots
General update (snapshot) that takes care of the several changes on disk that happened when moving around the webots directories.
Updated .gitignore to skip lyx backup files
Added Webots wbproj file (previously untracked)