chore: add sample for minRange on category scale (#873)

Author: kurkle

docs/.vuepress/config.js

@@ -134,6 +134,7 @@ module.exports = {
           title: 'Wheel Zoom',
           children: [
             'wheel/category',
+            'wheel/category-min-range',
             'wheel/log',
             'wheel/time',
             'wheel/over-scale-mode',

docs/samples/wheel/category-min-range.md

@@ -0,0 +1,98 @@
+# Category Scale + minRange
+
+```js chart-editor
+// <block:data:1>
+const DATA_COUNT = 20;
+const NUMBER_CFG = {count: DATA_COUNT, min: -100, max: 100};
+const data = {
+  labels: Utils.months({count: DATA_COUNT}),
+  datasets: [{
+    label: 'Dataset 1',
+    borderColor: Utils.randomColor(0.7),
+    backgroundColor: Utils.randomColor(0.5),
+    data: Utils.numbers(NUMBER_CFG),
+  }, {
+    label: 'Dataset 2',
+    borderColor: Utils.randomColor(0.7),
+    backgroundColor: Utils.randomColor(0.5),
+    data: Utils.numbers(NUMBER_CFG),
+  }, {
+    label: 'Dataset 3',
+    borderColor: Utils.randomColor(0.7),
+    backgroundColor: Utils.randomColor(0.5),
+    data: Utils.numbers(NUMBER_CFG),
+  }]
+};
+// </block:data>
+
+// <block:scales:2>
+const scaleOpts = {
+  grid: {
+    borderColor: Utils.randomColor(1),
+    color: 'rgba( 0, 0, 0, 0.1)',
+  },
+  title: {
+    display: true,
+    text: (ctx) => ctx.scale.axis + ' axis',
+  }
+};
+const scales = {
+  x: {
+    type: 'category',
+    min: 5,
+    max: 11,
+  },
+  y: {
+    type: 'linear'
+  },
+};
+Object.keys(scales).forEach(scale => Object.assign(scales[scale], scaleOpts));
+// </block:scales>
+
+// <block:config:0>
+const config = {
+  type: 'bar',
+  data: data,
+  options: {
+    scales: scales,
+    plugins: {
+      zoom: {
+        pan: {
+          enabled: true,
+          mode: 'x',
+          threshold: 5,
+        },
+        zoom: {
+          wheel: {
+            enabled: true
+          },
+          pinch: {
+            enabled: true
+          },
+          mode: 'x',
+        },
+        limits: {
+          x: {
+            minRange: 4
+          }
+        }
+      },
+    },
+  }
+};
+// </block:config>
+
+const actions = [
+  {
+    name: 'Reset zoom',
+    handler(chart) {
+      chart.resetZoom();
+    }
+  }
+];
+
+module.exports = {
+  actions,
+  config,
+};
+```