Combined Blog Feed

This commit addes a combined blog feed that shows all posts of all
subscribed blogs in the order the blog posts have been received.

For now, this commit also hides other blog functionality like adding
additional blogs and browsing individual blogs.

Closes #417

briar-android/src/org/briarproject/android/blogs/FeedController.java

@@ -0,0 +1,25 @@
+package org.briarproject.android.blogs;
+
+import org.briarproject.android.controller.ActivityLifecycleController;
+import org.briarproject.android.controller.handler.UiResultHandler;
+import org.briarproject.api.blogs.Blog;
+
+import java.util.Collection;
+
+public interface FeedController {
+
+	void onResume();
+	void onPause();
+
+	void loadPosts(
+			final UiResultHandler<Collection<BlogPostItem>> resultHandler);
+
+	void loadPersonalBlog(final UiResultHandler<Blog> resultHandler);
+
+	void setOnBlogPostAddedListener(OnBlogPostAddedListener listener);
+
+	interface OnBlogPostAddedListener {
+		void onBlogPostAdded(final BlogPostItem post);
+	}
+
+}