Tell segment IO whenever a page is loaded.  Once this works, we
can add more detailed instrumentation for events we care about.

Will be turned off in prod until the SEGMENT_IO_LMS feature flag is
set to True and a SEGMENT_IO_LMS_KEY is set.

The `FAVICON_PATH` setting determines the location of the favicon for
the site. It's automatically adjusted when a theme is enabled,
establishing the convention that themes will place their favicon in
`static/images/favicon.ico`.

Provide the appropriate switches to adjust based on whether or not a
theme (in particular, the Stanford theme) is enabled in the settings.
For now, these changes are very specific to Stanford. This is because
the template architecture needs some reworking to generalize nicely.

When an unauthenticated user clicks the registration button for a course, they
are redirected to the registration page with query params that are ultimately
included in the form that gets submitted so they can be enrolled in the course
upon successful registration. The header login button is fixed to pass the same
query parameters to the login page so the user can be enrolled in the course
upon successful login.

Switch timed_module to store location, and use to navigate from timer when timer displays on non-exam course pages.

This reverts commit 2b5e8a49, reversing
changes made to db0549be.

Removed a bunch of non-necessary javascript from homepage. Most of it was put back in courseware. A new PIPELINE_JS group 'courseware' was created, for pipeline javascript files that should only be in the courseware.

Rearranged more images, made some smaller, made some slight changes to the design on the homepage and made all edX proper case