re-add OSX troubleshooting instructions (not sure how they got lost)
re-add OSX troubleshooting instructions (not sure how they got lost)

matrix-org/synapse,matrix-org/synapse,illicitonion/synapse,howethomas/synapse,matrix-org/synapse,howethomas/synapse,rzr/synapse,TribeMedia/synapse,iot-factory/synapse,matrix-org/synapse,howethomas/synapse,illicitonion/synapse,iot-factory/synapse,illicitonion/synapse,TribeMedia/synapse,rzr/synapse,illicitonion/synapse,matrix-org/synapse,TribeMedia/synapse,matrix-org/synapse,iot-factory/synapse,iot-factory/synapse,TribeMedia/synapse,rzr/synapse,rzr/synapse,rzr/synapse,howethomas/synapse,howethomas/synapse,illicitonion/synapse,TribeMedia/synapse,iot-factory/synapse