Redirect to login if not authenticated

If a user isn't authenticated, redirect to login akin to the Gitweb
integration.  This avoids leaking information about repository
existence, but gives users a chance to log in if they have not yet.
This is especially useful as sessions expire: if the first page
viewed is Gitiles, they would receive a "Not Found" page instead of
creating a new session.

Change-Id: If06ec2a0ed85533b81a0e70d3545ee5129c7e3a6
3 files changed
tree: 8595b6fbd1151cf01ff01f137fbba43d7a19fe7a
  1. .gitignore
  2. BUCK
  4. src/