Add start & end gcode to UM2 depending on gcode flavor

CURA-580

resources/definitions/ultimaker2.def.json

@@ -18,10 +18,12 @@
     },
     "overrides": {
         "machine_start_gcode" : {
-            "default_value": ""
+            "default_value": "",
+            "value": "\"\"  if machine_gcode_flavor == \"UltiGCode\" else \"G21 ;metric values\\nG90 ;absolute positioning\\nM82 ;set extruder to absolute mode\\nM107 ;start with the fan off\\nG1 X10 Y0 F4000;move X/Y to min endstops\\nG28 Z0 ;move Z to bottom endstops\\nG1 Z15.0 F9000 ;move the platform to 15mm\\nG92 E0 ;zero the extruded length\\nG1 F200 E10 ;extrude 10 mm of feed stock\\nG92 E0 ;zero the extruded length again\\nG1 F9000\\n;Put printing message on LCD screen\\nM117 Printing...\""
         },
         "machine_end_gcode" : {
-            "default_value": ""
+            "default_value": "",
+            "value": "\"\"  if machine_gcode_flavor == \"UltiGCode\" else \"M104 S0 ;extruder heater off\\nM140 S0 ;heated bed heater off (if you have it)\\nG91 ;relative positioning\\nG1 E-1 F300  ;retract the filament a bit before lifting the nozzle, to release some of the pressure\\nG1 Z+0.5 E-5 X-20 Y-20 F9000 ;move Z up a bit and retract filament even more\\nG28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way\\nM84 ;steppers off\\nG90 ;absolute positioning\""
         },
         "machine_width": {
             "default_value": 223