Added PreferenceUtiliy class
Added FindChannelsCommand
SearchFragment uses FindChannelsCommand
Added CookieCommand class
Added URLCommand interface
Added GetItemsCommand
ChannelActivity uses GetItemsFromChannelCommand
Refactored getURL() method
Added SwipeRefreshLIstFragment class
Added swipe refresh to ChannelFragment and ItemFragment
Fixed work with shared preferences
Fixed CookieCommand
Added prototypes of SignIn and SignUp commands
Added SignIn, SignUp and LogOut functionality
Added prototype of MarkItemAsRead command
Added "Mark as read" button
Fixed server adress