[builder] fix bpymorse.set_viewport_perspective
[pymorse] fix missing chunk in asynchat patch
[builder] Set ControlType to Position for PR2 robot

Reported by Omar Adair Islas Ramírez
[doc] Fix the ControlType for XYW Motion for PR2

Reported by Omar Adair Islas Ramírez
[testing] Relax precision on YARP tests

It always was less precise than socket one, but was not properly bumped
when the controller changes (to use proper physics)
[builder] Set the gravity in a consistent way

Gravity is stored in multiples place in Blender, set "all" of them.
Make sure the default is 9.81, as written in the documentation.

Fix #514
[builder] Make sure the laser are not rendered

Previously, they can appear in a videocamera fov