Include DNS rules in FAQ

Closes #259
2 jobs for master in 3 minutes and 26 seconds (queued for 4 minutes and 40 seconds)
Status Name Job ID Coverage
  Build
failed build_fdroid #20786

00:01:27

passed build_release #20787

00:02:06

 
Name Stage Failure
failed
build_fdroid Build
* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.6/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 1m 21s
25 actionable tasks: 24 executed, 1 up-to-date
ERROR: Job failed: exit code 1