renamed selectors for login menu, changed naming of navbar selector to session-menu, tweaked login menu selector to be listened to via event delegation
if user has session when first loading site (i.e. logged-in), the logout button will be present instead of login menu button
upon successful logout, logout button image changes to login button image
logout emptys contents of #current-user-data div which contained script tag or userData. Also, userData global variable set to undefined
upon login or sign-up, login menu button changes to a logout button
fixed jasmine test to reflect current implementation
Merge pull request #33 from pocket-gophers-2014/logout

Logout