Add default sample time BallAndBeam

src/LabProcesses.jl

@@ -37,10 +37,12 @@ finalize(p::AbstractProcess)    = error("Function not implemented for $(typeof(p
 struct BallAndBeam <: PhysicalProcess
     h::Float64
 end
+BallAndBeam() = BallAndBeam(0.01)
 
 struct BallAndBeamSimulator <: SimulatedProcess
     h::Float64
 end
+BallAndBeamSimulator() = BallAndBeamSimulator(0.01)
 
 const BallAndBeamType = Union{BallAndBeam, BallAndBeamSimulator}
 num_outputs(p::BallAndBeamType) = 2