Improve feedback when fetching data (block UI). issue#36
Improve performance when filtering large number of posts. issue#38
Ensure checker can't be used if the admin feed is unavailable. issue#30
UI should be unblocked also when ajax errors occurs. issue#36
Clarify error when feed can't be parsed. issue#48
Update error message (when feed can't be parsed). issue#48
Filter out property errors regardless of namespace. issue#59
Add button to display all rows. issue#45
Ensure button-to-display-all-rows is IE8-compatible. issue#45
Disable submit button if feedUrl is empty. issue#47
Trimmed down form layout. issue#35
Trim down checker summary and source layout. issue#35
Trim down checker filter layout. issue#35
Merge branch 'feature/improve_checker' into develop