Issue #30 : Handle the NOT_LOGGED_IN errors that can come from tt-rss backends. It currently asks the user to type the login/password again, which is not ideal. But at least he can access his unread articles again.
Issue #30 : Keep the username in localStorage, so that the user does not have to type it again in case his session has expired
+ also fill the login form with the localStorage values when the user chooses to logout
Issue #30 : Fix a typo in function name
Issue #30 : Avoid displaying "undefined" for username when it was not yet stored in the localStorage
Merge pull request #35 from mossroy/master

Issue #30 : Handle the NOT_LOGGED_IN errors that can come from tt-rss backends.