added/updated meta description & content description

Author: bobkovalex

index.html

@@ -4,7 +4,7 @@
 		<meta charset="utf-8">
 		<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
 		<meta name="description" content="View documents in .NET and Java with an advanced document viewer API's">
-		<title>GroupDocs.Viewer - Document Viewer</title>
+		<title>GroupDocs.Viewer - Document Viewer - View DOCX, PDF, XLSX and PPTX</title>
 		<link href="favicon.ico?v1.0" rel="shortcut icon" type="image/vnd.microsoft.icon">
 		<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.4.2/css/all.css" integrity="sha384-/rXc/GQVaYpyDdyxK+ecHPVYJSN9bmVFBvjA/9eOB+pb3F2w2N6fc5qB9Ew5yIns" crossorigin="anonymous">
 		<link rel="stylesheet" type="text/css" href="resources/css/groupdocs.viewer.css"/>