Update backgrounds for navigationBar and toolbar
Load table view cells from xib files
Fix subview layout in table veiw cell

* Fix table view separator
Modify the design of feed item cells
Merge pull to refresh into ICRSSViewController
Modify the design of navigation bar
Modify the design of ICFeedTitleCell

* Remove .xib file
Modify the design of ICFeedDateCell

* Remove .xib file
Modify the design of ICFeedTextCell

* Remove .xib file
Modify the design of ICFeedLinkCell

* Remove .xib file