Reset posts view on iPad when logging out.

It used to show the last thread you were reading behind the login form.

The notification stuff is to deal with the posts view's attempt to mark posts
as read when it disappears.
instancetype is cool
Fix logging in and use proper error codes.

The SA Forums recently changed how logging in works in a way that affects how
we check for success or failure.

We were also using made up error codes in the NSCocoaErrorDomain instead of
making our own proper AwfulErrorDomain. That was dumb and is now fixed.
Note for handier logging in in the future.
Fix crash in threads with ignored users.

Our ticket to learning a post's author's user ID was the "profile" link at the
bottom. This isn't displayed for ignored users' posts, and the nil was passed
to -[NSRegularExpression firstMatchInString:options:range:] which throws
exceptions on nils.
Add thread tag "chooch".
Stop passing nil to NSRegularExpression methods.

They blow up getting nils.
Log in using https.
Relayout title in Awful Browser on change.

Make sure it's nicely centred as we like it.
Add tag byob-xfile
Update AFNetworking to 1.1.0.

For fixes to compiler warnings.
Xcode 4.6 project updates and fix new warnings.

Xcode suggested the updates to project.pbxproj. The rest of the fixes are for
new warnings.
Post notifications asynchronously on main queue.

No need for observers to jump through hoops to get on the main queue.
Remove notification main queue contortions.

All of our notifications are always posted from the main queue.
Check for new tags up to thrice as often.
Simplify showing new thread tags.

Not sure why all that bookkeeping seemed necessary. Just reload the cells that
might have been affected and call it done.
Remove dead code.
Fix NSURLErrorDomain error -999.

Since networking isn't always up when we refresh a list in -viewWillAppear:, we
also refresh when network reachability changes. If this happens quick enough,
we could end up refreshing a second time before the first refresh is done. Now
we only refresh on reachability changes if we're not already refreshing.
Add LF-dad thread tag

Apparently there is a phiz-dad and an LF-dad. They are the exact same
image, just with different names. We had phiz but not LF.
Update hpple.