Fixes a bug that the 'serialport:close' socket event was never fired
Fixes a bug that the 'serialport:close' socket event was never fired

cncjs/cncjs,cheton/piduino-grbl,cheton/cnc,cheton/cnc,cheton/cnc.js,cheton/cnc.js,cheton/cnc,cncjs/cncjs,cncjs/cncjs,cheton/cnc.js,cheton/piduino-grbl,cheton/piduino-grbl