Use single quotes in bearer token error

Using double quotes means that they have to be escaped in the JSON
output that we return to users. It's nicer to use single quotes so
that they're easier to read in the JSON.
Remove RAW_QUERIES_ALLOWED configuration

This hasn't been used since at least 65fe1d3a58dc0b4cad7caba753fd28a4af2fee6e
in September 2013.
WIP