Move platform offset to metadata

Also removed the setting from fdmprinter just to be clear.

Contributes to issue CURA-1278.

resources/definitions/bq_witbox_2.def.json

@@ -9,7 +9,8 @@
         "manufacturer": "BQ",
         "category": "Other",
         "file_formats": "text/x-gcode",
-        "platform": "bq_witbox_platform.stl"
+        "platform": "bq_witbox_platform.stl",
+        "platform_offset": [0, -145, -38]
     },
 
     "overrides": {
@@ -37,9 +38,6 @@
         "machine_gcode_flavor": {
             "default_value": "RepRap"
         },
-        "machine_platform_offset": {
-            "default_value": [0, -145, -38]
-        },
         "material_print_temperature": {
             "default_value": 210
         },

resources/definitions/innovo_inventor.def.json

@@ -9,7 +9,8 @@
         "manufacturer": "Innovo",
         "category": "Other",
         "file_formats": "text/x-gcode",
-        "platform": "inventor_platform.stl"
+        "platform": "inventor_platform.stl",
+        "platform_offset": [-180, -0.25, 160]
     },
 
     "overrides": {
@@ -61,9 +62,6 @@
         "machine_end_gcode": {
             "default_value": "M104 S0\nG91 ; relative positioning\nG1 E-2 F5000; retract 2mm\nG28 Z; move bed down\nG90 ; absolute positioning\nM84   ; disable motors"
         },
-        "machine_platform_offset": {
-            "default_value": [-180, -0.25, 160]
-        },
         "layer_height": {
             "default_value": 0.15
         },

resources/definitions/maker_starter.def.json

@@ -4,9 +4,9 @@
     "name": "3DMaker Starter",
     "inherits": "fdmprinter",
     "metadata": {
-        "visible": true,
         "author": "tvlgiao",
         "manufacturer": "3DMaker",
+        "category": "Other",
         "file_formats": "text/x-gcode;application/x-stl-ascii;application/x-stl-binary;application/x-wavefront-obj",
         "icon": "icon_ultimaker2.png",
         "platform": "makerstarter_platform.stl"
@@ -58,9 +58,6 @@
         "machine_disallowed_areas": {
             "default_value": []
         },
-        "machine_platform_offset": {
-            "default_value": [0, 0, 0]
-        },
         "machine_nozzle_tip_outer_diameter": {
             "default_value": 1
         },

resources/definitions/ultimaker2.def.json

@@ -10,7 +10,8 @@
         "file_formats": "text/x-gcode",
         "icon": "icon_ultimaker2.png",
         "platform": "ultimaker2_platform.obj",
-        "platform_texture": "Ultimaker2backplate.png"
+        "platform_texture": "Ultimaker2backplate.png",
+        "platform_offset": [9, 0, 0]
     },
     "overrides": {
         "machine_start_gcode" : {
@@ -69,9 +70,6 @@
               [[-115, -112.5], [-115, -104.5], [ -84, -104.5], [ -82, -112.5]],
               [[ 115, -112.5], [ 108, -112.5], [ 110, -104.5], [ 115, -104.5]]
         ]},
-        "machine_platform_offset": {
-            "default_value": [9, 0, 0]
-        },
         "machine_nozzle_tip_outer_diameter": {
             "default_value": 1
         },

resources/definitions/ultimaker2_go.def.json

@@ -10,7 +10,8 @@
         "file_formats": "text/x-gcode",
         "icon": "icon_ultimaker2.png",
         "platform": "ultimaker2go_platform.obj",
-        "platform_texture": "Ultimaker2Gobackplate.png"
+        "platform_texture": "Ultimaker2Gobackplate.png",
+        "platform_offset": [0, 0, 0]
     },
 
     "overrides": {
@@ -34,8 +35,5 @@
                 [[ 60, -60], [ 33, -60], [ 35, -52], [ 60, -52]]
             ]
         },
-        "machine_platform_offset": {
-            "default_value": [0, 0, 0]
-        }
     }
 }

resources/machines/fdmprinter.json

@@ -121,15 +121,6 @@
             "default": [],
             "global_only": true
         },
-        "machine_platform_offset": {
-            "description": "Where to display the platform mesh.",
-            "default": [
-                0,
-                0,
-                0
-            ],
-            "global_only": true
-        },
         "machine_head_polygon": {
             "description": "A 2D silhouette of the print head (fan caps excluded).",
             "type": "polygon",