Update htmlhint.json (SchemaStore#4739)

Add additional rules

Author: coliff

src/schemas/json/htmlhint.json

@@ -17,6 +17,11 @@
       "type": "boolean",
       "default": false
     },
+    "attr-sorted": {
+      "description": "Attributes should be sorted in an order.",
+      "type": "boolean",
+      "default": false
+    },
     "attr-unsafe-chars": {
       "description": "Attribute value can't not use unsafe chars.",
       "type": "boolean",
@@ -32,13 +37,23 @@
       "type": "boolean",
       "default": false
     },
+    "attr-value-single-quotes": {
+      "description": "Attribute value must closed by single quotes.",
+      "type": "boolean",
+      "default": false
+    },
+    "attr-whitespace": {
+      "description": "No leading or trailing spaces inside attribute values.",
+      "type": "boolean",
+      "default": false
+    },
     "doctype-first": {
       "description": "Doctype must be first.",
       "type": "boolean",
       "default": false
     },
     "doctype-html5": {
-      "description": "Doctype must be html5.",
+      "description": "Doctype must be HTML5.",
       "type": "boolean",
       "default": false
     },