Changed order of operations in CSpace::Update().

Before Draw was executed after Act, making it difficult to see exactly on what sensor values the robot was about to act.

Now Act is performed first, then Sense and finally ControlStep. In this way, Draw displays the latest state available to the robot.

Commented out CSpaceMultiThreadBalanceLength because it does not work. Bug fixes will follow.
Fixed bug in concurrent access to CDynamics2D::CheckIntersectionWithRay().

Before, when using threads, checking for ray intersections created a nasty error in Chipmunk that was due to the space being locked but accessed concurrently. Now a mutex protects access to this function.
Restored full functionality of the 'balance_length' thread scheduling method.
Fixed the logic of CLoopFunctions::PreStep() and CLoopFunctions::PostStep().

Now CLoopFunctions::PreStep() is executed before sense/control step, and CLoopFunctions::PostStep() is executed right after it.
Fixed minor compilation warning.
Added bash completion script
Bash completion script installed in share/argos3
Fixed little bug in the simulator command line argument parser
Minor change to a message
Added creation of link to bash-completion in Linux-based installation scripts
Merge branch 'master' into multibody

Conflicts:
	src/core/simulator/space/space.cpp