Organize Toolbox (marketplace) qml files according to type

CURA-6569

plugins/Toolbox/resources/qml/components/ToolboxDownloadsGrid.qml

@@ -0,0 +1,45 @@
+// Copyright (c) 2018 Ultimaker B.V.
+// Toolbox is released under the terms of the LGPLv3 or higher.
+
+import QtQuick 2.10
+import QtQuick.Controls 2.3
+import UM 1.1 as UM
+
+Column
+{
+    property var heading: ""
+    property var model
+    id: gridArea
+    height: childrenRect.height + 2 * padding
+    width: parent.width
+    spacing: UM.Theme.getSize("default_margin").height
+    padding: UM.Theme.getSize("wide_margin").height
+    Label
+    {
+        id: heading
+        text: gridArea.heading
+        width: parent.width
+        color: UM.Theme.getColor("text_medium")
+        font: UM.Theme.getFont("large")
+        renderType: Text.NativeRendering
+    }
+    Grid
+    {
+        id: grid
+        width: parent.width - 2 * parent.padding
+        columns: 2
+        columnSpacing: UM.Theme.getSize("default_margin").height
+        rowSpacing: UM.Theme.getSize("default_margin").width
+        Repeater
+        {
+            model: gridArea.model
+            delegate: Loader
+            {
+                asynchronous: true
+                width: Math.round((grid.width - (grid.columns - 1) * grid.columnSpacing) / grid.columns)
+                height: UM.Theme.getSize("toolbox_thumbnail_small").height
+                source: "ToolboxDownloadsGridTile.qml"
+            }
+        }
+    }
+}