Use MD5 hash for basic auth password

Set environment variable AUTH_PASS on production server to an MD5 hash
of the password. To set the password to 'hello' you would execute the
following in a rails console:

Digest::MD5.hexdigest('hello')

Copy the output to the environment variable on the server. To better
secure the password, save the environment settings on the server in a
file readable only by the apache or root user.