Don't forbid '_' in metric basenames any more, to allow things like foo_time
Don't forbid '_' in metric basenames any more, to allow things like foo_time

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