fix(demo): fix links to documentation

I deleted wiki because it was the exact duplicate of the typings files
produced by gallery's build. But now the links to docs pointed nowhere.
I decided to point them at the gallery component since it has pretty good
descriptions of the API.

apps/demo/src/app/app.component.html

@@ -2,7 +2,7 @@
 
 <aside>
   <div class="menu-heading"><a href="#usage">Usage</a></div>
-  <div class="menu-heading"><a href="#demos">Demos</a></div>
+  <div class="menu-heading"><a href="#demos">Showcases</a></div>
   <ul>
     <li><a href="#demo-responsive">Responsive</a></li>
     <li>
@@ -19,7 +19,9 @@
   <div class="menu-heading">Misc</div>
   <ul>
     <li>
-      <a href="https://github.com/daelmaak/ngx-gallery/wiki" target="_blank"
+      <a
+        href="https://github.com/daelmaak/ngx-gallery/blob/master/libs/gallery/src/lib/components/gallery/gallery.component.ts"
+        target="_blank"
         >Documentation</a
       >
     </li>
@@ -49,7 +51,7 @@ <h4>Template</h4>
       </div>
     </div>
 
-    <h2 id="demos">Demos</h2>
+    <h2 id="demos">Showcases</h2>
 
     <app-showcase
       id="demo-responsive"
@@ -66,9 +68,10 @@ <h2 id="demos">Demos</h2>
     >
       <div subheading>
         You can also use your custom templates for items, loading screen,
-        loading errors, thumbnails and more. Find out how in the
+        loading errors, thumbnails and more. Find out which templates can be
+        used to customize in the
         <a
-          href="https://github.com/daelmaak/ngx-gallery/wiki/Gallery-API"
+          href="https://github.com/daelmaak/ngx-gallery/blob/master/libs/gallery/src/lib/components/gallery/gallery.component.ts"
           target="_blank"
           >documentation.</a
         >
@@ -116,7 +119,7 @@ <h2 id="demos">Demos</h2>
       <div subheading>
         Some options like custom templates are missing. Check them out in the
         <a
-          href="https://github.com/daelmaak/ngx-gallery/wiki/Gallery-API"
+          href="https://github.com/daelmaak/ngx-gallery/blob/master/libs/gallery/src/lib/components/gallery/gallery.component.ts"
           target="_blank"
           >documentation.</a
         >