Adding support Tevo Black Widow

Definition for _Tevo Black Widow_ from the user manual.

resources/definitions/tevo_blackwidow.def.json

@@ -0,0 +1,57 @@
+{
+    "version": 2,
+    "name": "Tevo Black Widow",
+    "inherits": "fdmprinter",
+    "metadata": {
+        "visible": true,
+        "author": "TheTobby",
+        "manufacturer": "Tevo",
+        "file_formats": "text/x-gcode",
+        "icon": "icon_ultimaker2",
+        "platform": "prusai3_platform.stl"
+    },
+    "overrides": {
+        "machine_name": {
+            "default_value": "Tevo Black Widow"
+        },
+        "machine_heated_bed": {
+            "default_value": true
+        },
+        "machine_width": {
+            "default_value": 350
+        },
+        "machine_height": {
+            "default_value": 250
+        },
+        "machine_depth": {
+            "default_value": 250
+        },
+        "machine_center_is_zero": {
+            "default_value": false
+        },
+        "machine_nozzle_size": {
+            "default_value": 0.4
+        },
+        "material_diameter": {
+            "default_value": 1.75
+        },
+        "gantry_height": {
+            "default_value": 0
+        },
+        "machine_gcode_flavor": {
+            "default_value": "RepRap (Marlin/Sprinter)"
+        },
+        "speed_travel": {
+            "default_value": 70
+        },
+        "speed_print": {
+            "default_value": 60
+        },
+        "machine_start_gcode": {
+            "default_value": "M280 P0 S160 ; release BLTouch alarm (OK to send for Non BLTouch)\M420 Z2 ; set fade leveling at 2mm for BLTouch (OK to send for Non BLTouch)\G28 ; home all\G29 ; probe bed\G92 E0 ;zero the extruded length\G1 X0.0 Y50.0 Z10.0 F3600\; perform wipe and prime\G1 Z0.0 F1000\G1 Z0.2 Y70.0 E9.0 F1000.0 ; prime\G1 Y100.0 E12.5 F1000.0 ; prime\G92 E0 ; zero extruder again\M117 Printing..."
+        },
+        "machine_end_gcode": {
+            "default_value": "G92 E0 ; zero the extruded length again\G1 E-1.5 F500 ; retract the filament to release some of the pressure\M104 S0 ; turn off extruder\M140 S0 ; turn off bed\G28 X0 ; home X axis\G1 Y245 ; move Y axis to end position\M84 ; disable motors\M107 ; turn off fan"
+        }
+    }
+}