title: Is there a Bug in motor.run_target command?
body: <p>MicroPython 1.0.0, 
  ev3dev Linux echo 4.14.96-ev3dev-2.3.2-ev3 #1 PREEMPT Sun Jan 27 21:27:35 CST 2019 armv5tejl GNU/Linux</p>
  
  <pre><code>#!/usr/bin/env pybricks-micropython
  from pybricks import ev3brick as brick
  from pybricks.ev3devices import Motor
  from pybricks.parameters import Port, Stop
  from pybricks.tools import print, wait
  
  leftMotor = Motor(Port.B)
  rightMotor = Motor(Port.C)
  
  # speed range -100 to 100
  
  def leftWheel():
      leftMotor.run_target(50, 360, Stop.COAST, True)
  
  def rightWheel():
      rightMotor.run_target(50, -360, Stop.COAST, True)
  
  leftWheel()
  rightWheel()
  </code></pre>
  
  <p>This works if I use True, so it runs left then right. But if I set it false it does nothing. [should run both in parallel]</p>