Updates no results view.

Shows "Fetching posts..." status and fixes an issue with the no posts message flickering briefly.
Merge branch 'develop' of github.com:wordpress-mobile/WordPress-iOS into issues/1663-animated-paper-issue

Conflicts:
	WordPress/Classes/ViewRelated/Reader/ReaderPostsViewController.m
Merge pull request #2025 from wordpress-mobile/issues/1663-animated-paper-issue

Updates no results view.