Style LMS header, footer and nav for Bootstrap.

cms/envs/devstack.py

common/test/acceptance/pages/lms/dashboard.py

lms/envs/common.py

lms/envs/devstack.py

lms/static/js/user_dropdown_v1.js

lms/static/sass/bootstrap/_footer.scss

lms/static/sass/bootstrap/_layouts.scss

lms/static/sass/bootstrap/_navigation.scss

lms/static/sass/bootstrap/_variables.scss

lms/static/sass/bootstrap/lms-main-bootstrap.scss

lms/static/sass/shared/_header.scss

lms/templates/footer.html

lms/templates/header.html

lms/templates/main.html

lms/templates/navigation.html

lms/templates/navigation/bootstrap/navbar-authenticated.html

lms/templates/navigation/bootstrap/navbar-logo-header.html

...plates/navigation/bootstrap/navbar-not-authenticated.html

lms/templates/navigation/navbar-authenticated.html

lms/templates/navigation/navbar-logo-header.html