Checks for empty string when building featured image URL.
Return the count of returned posts instead of a boolean.
Entity name from fetch request. Support controllerWillChangeContent
ReaderPostViewController no longer inherits from WPTableViewController

ReaderPostViewController inherits from UITableViewController
WPTableViewHandler and WPContentSyncHelper are implemented
Code organization, styling and some clean up of dead code.

TODOs:
NoResultsView behavior needs to be restored.
Cell heights need to be updated when rotating
Refresh control behavior needs to be sorted out.
State restoration needs to be restored.
Adds support for detecting scrolling.
Removes unnecessary calculation when determining height.
Hides refresh control when scrolling. Fixes row height caching.
Improvements to row caching.

Normalizes method naming convention.
Updates cached row height invalidation to match approach in WPTableViewController. Props @jleandroperez
Reload the cell vs configuring the cell.

The type of cell may have changed, so its better to reload than to assume its the same kind and just reconfigure.
First pass at animated cell changes.

Does not handle the desired behavior when refreshing the list
Needs more testing for edge cases.
First pass at preserving post list offset during pull to refresh.

Allows for inserting content above the current visible cell without jumping the table view.
Restores state restoration.
Restores no results view behavior.
Reimplement autosyncing
Remove NSLog statement
Fix edge cases where row offset would not be preserved.
Fixes footer spinner placement.
Fixes an issue where valid posts would be deleted.
Fixes layout issues.

Fixes a potential visual glitch in the post list after changing topics.
Avoid animating new cells via a load more request.
Fixes an case where the isScrolling flag might not clear.