In FAQ section 13.24, the Apache 2 RequestHeader configuration syntax is incorrect

[buzzerrookie]

In FAQ section 13.24, the Apache 2 configuration syntax is incorrect. From the Apache doc for RequestHeader, there is no equal sign between RequestHeader and set. The example configuration RequestHeader=set X-Forwarded-Prefix "/custom-path" is incorrect and leads to error when starting Apache 2.

[buzzerrookie]

I've created a PR to fix this, #45