fixed issue where including metaInfo with the same script across multiple components on the same page includes it multiple times. this will de-dupe any of the same tags so that only one is ever inserted

src/client/updaters/updateTags.js

@@ -18,6 +18,20 @@ export default function _updateTags (options = {}) {
     const newTags = []
     let indexToDelete
 
+	 if (tags.length > 1) {
+		 // remove duplicates that could have been found by merging tags
+		 // which include a mixin with metaInfo and that mixin is used
+		 // by multiple components on the same page
+		 const found = [];
+		 tags = tags.map(x => {
+			 const k = JSON.stringify(x);
+			 if (found.indexOf(k) < 0) {
+				 found.push(k);
+				 return x;
+			 }
+		 }).filter(x => x);
+	 }
+
     if (tags && tags.length) {
       tags.forEach((tag) => {
         const newElement = document.createElement(type)