issue/2119-reader-message-bar

Fix #2119 - As you can see from the commit history, I began this branch by rewriting the message bar as a custom view and having it behave somewhat differently than it currently does.

But in the end I decided the message bar was simply overkill. It's only used in one place - the "Tags & Blogs" screen in the reader - and doesn't offer anything a toast doesn't except a non-standard UI.

So in the end I replaced the whole thing with toasts that appear at the bottom (just above the EditText).