Close #7, authenticate against salt-api

requirements.txt

salt_observer/assets/img/blank_user.gif

salt_observer/assets/js/base.js

salt_observer/assets/less/base.less

salt_observer/assets/less/login.less

salt_observer/assets/less/main.less

salt_observer/assets/less/sidebar.less

salt_observer/backends.py

salt_observer/cherry.py

salt_observer/forms.py

salt_observer/settings.py

salt_observer/static/css/main.min.css

salt_observer/static/img/blank_user.gif

salt_observer/static/js/base.min.js

salt_observer/templates/auth/login.html

salt_observer/templates/base.html

salt_observer/templates/dashboard.html

salt_observer/templates/domain/detail.html

salt_observer/templates/domain/list.html

salt_observer/templates/minion/detail.html