Added freecad blog tab to start page

src/Mod/Start/StartPage/StartPage.css

@@ -1,8 +1,15 @@
+html{
+    height: 100%;
+    display: flex;
+    flex-direction: column;
+}
+
 body {
     background: BACKGROUND;
     color: BGTCOLOR;
     font-family: FONTFAMILY;
     font-size: FONTSIZE;
+    height: 100%;
 }
 OVERFLOW
 a, a:link, a:visited {
@@ -37,7 +44,8 @@ hr {
     vertical-align:middle;
 }
 .container {
-    margin: 2%
+    margin: 2%;
+    height: 95%;
 }
 ul.tabs {
     margin: 9px 0;
@@ -198,3 +206,16 @@ ul.workbenches li, ul.addonslist li {
     border-radius: 3px;
     min-height: 300px;
 }
+
+
+.iframe {
+    display:block;
+    margin: auto;
+    text-align: center;
+    width:50%;
+    height:100%;
+}
+
+.iframecontainer {
+    height:90%;
+}

src/Mod/Start/StartPage/StartPage.html

@@ -21,6 +21,7 @@
                 <li><a id="htab1" class="active" onClick="toggle('tab1')" href="#">T_DOCUMENTS</a></li>
                 <li><a id="htab2" onClick="toggle('tab2')" href="#">T_HELP</a></li>
                 <li><a id="htab3" onClick="toggle('tab3')" href="#">T_ACTIVITY</a></li>
+                <li><a id="htab4" onClick="toggle('tab4')" href="#">BLOG</a></li>
             </ul>
             <div id="tab1" class="panel">
                 
@@ -157,6 +158,10 @@
 
             </div>
 
+            <div id="tab4" class="panel hidden iframecontainer">
+                <iframe src="https://blog.freecad.org/" title="Freecad Blog" frameborder="0" class="iframe" ></iframe> 
+            </div>
+
         </div>
     </body>
 </html>