Login screen (front-end)

The login screen uses transparency to provide a rich UI
experience. A vivid image and a sober login screen gives
good result.

CSS code provided by resources/assets/less/login.less.

The base wireframe is inspired of the Google login screen,
as interpreted by cesiztel:
http://bootsnipp.com/snippets/featured/google-style-login-extended-with-html5-localstorage

Beta testers: Okki, Kumkum, Aelfgar, Fauve.