Highlight the upload by sharing feature

This resolves one of the items in commons-app#19.

Author: sivaraam

images/upload-via-sharing-v2.jpeg

@@ -147,6 +147,27 @@ <h3 class="item-header">Categorize your photos</h3>
                         </p>
                     </div>
                 </div>
+                <div class="col-lg-6 col-lg-pull-6 col-sm-12">
+                    <div class="item">
+                        <div class="item-image">
+                            <img class="feature-image"
+                                 src="images/upload-via-sharing.jpeg"
+                                 alt="Commons app in the list of apps to share an image."
+                                 title="Commons app in the list of apps to share an image."
+                            />
+                        </div>
+                        <div class="hover-bar"></div>
+                        <h3 class="item-header">Upload by sharing</h3>
+                        <p class="item-text">
+                            Start uploading images to Commons just by
+                            <em>sharing</em> them from your favourite
+                            gallery app. Just choose the Commons app
+                            from the list of apps and you'll directly
+                            get into uploading the image using the
+                            Commons app.
+                        </p>
+                    </div>
+                </div>
                 <div class="col-lg-6 col-lg-push-6 col-sm-12">
                     <div class="item">
                         <div class="item-image">