docs: change Get Started link and invalid link

Also add a link to the releases for reference.

Author: hansl

etc/cli.angular.io/index.html

@@ -39,7 +39,8 @@
         </nav>
         <div class="mdl-layout-spacer"></div>
         <nav class="mdl-navigation">
-            <a class="mdl-navigation__link" href="https://github.com/angular/angular-cli"> Get Started </a>
+            <a class="mdl-navigation__link" href="https://github.com/angular/angular-cli/releases"> Releases </a>
+            <a class="mdl-navigation__link" href="https://github.com/angular/angular-cli/wiki"> Get Started </a>
         </nav>
     </div>
     </div>
@@ -58,7 +59,7 @@
         <div class="mdl-cell mdl-cell--6-col-desktop mdl-cell--12-col-tablet mdl-cell--12-col-phone">
             <h4 class="">Angular CLI</h4>
             <h5 class="tagline">A command line interface for Angular</h5>
-            <a href="https://github.com/angular/angular-cli" class="mdl-typography--font-regular cta mdl-button mdl-button--raised mdl-button--primary">
+            <a href="https://github.com/angular/angular-cli/wiki" class="mdl-typography--font-regular cta mdl-button mdl-button--raised mdl-button--primary">
                 Get Started
             </a>
         </div>
@@ -93,7 +94,7 @@ <h4>Test, Lint, Format</h4>
 
 
     <div class="button-container mdl-cell mdl-cell--12-col-desktop center">
-        <a href="https://github.com/angular/angular-cli" class="cta-button mdl-typography--font-regular mdl-button mdl-button--raised mdl-button--accent">
+        <a href="https://github.com/angular/angular-cli/wiki" class="cta-button mdl-typography--font-regular mdl-button mdl-button--raised mdl-button--accent">
             Get Started
         </a>
     </div>
@@ -108,7 +109,7 @@ <h4>Test, Lint, Format</h4>
             </div>
             <div class="mdl-cell mdl-cell--2-col mdl-cell--12-col-tablet footer-links">
                 <ul class="footer-links">
-                    <li> <a class="" href="https://wwww.angular.io">Learn Angular</a> </li>
+                    <li> <a class="" href="https://www.angular.io">Learn Angular</a> </li>
                 </ul>
             </div>
             <div class="mdl-cell mdl-cell--9-col">