Improve Docker no-auth mode.

Remove use of environment variable, instruct users to run a specific
command instead.

docker/2.0-openssl/README.md

@@ -25,12 +25,10 @@ context of a container, this means you would normally need to provide a
 configuration file with your settings.
 
 If you wish to run mosquitto without any authentication, and without setting
-any other configuration options, you can do so by setting an environment
-variable when creating the container: `NO_AUTHENTICATION=1`. Doing this will
-ignore any configuration file you provide.
-
+any other configuration options, you can do so by using a configuration
+provided in the container for this purpose:
 ```
-docker run -it -p 1883:1883 -e NO_AUTHENTICATION=1 eclipse-mosquitto:<version>
+docker run -it -p 1883:1883 eclipse-mosquitto:<version> mosquitto -c /mosquitto-no-auth.conf
 ```
 
 ## Configuration

docker/2.0-openssl/docker-entrypoint.sh

@@ -7,11 +7,4 @@ if [ "$user" = '0' ]; then
 	[ -d "/mosquitto" ] && chown -R mosquitto:mosquitto /mosquitto || true
 fi
 
-if [ "$NO_AUTHENTICATION" = "1" ] && [ "$*" = '/usr/sbin/mosquitto -c /mosquitto/config/mosquitto.conf' ]; then
-	# The user wants to run Mosquitto with no authentication, but without
-	# providing a configuration file. Use the pre-provided file for this.
-	exec /usr/sbin/mosquitto -c /mosquitto-no-auth.conf
-else
-	# Execute whatever command is requested
-	exec "$@"
-fi
+exec "$@"

docker/2.0/README.md

@@ -25,12 +25,10 @@ context of a container, this means you would normally need to provide a
 configuration file with your settings.
 
 If you wish to run mosquitto without any authentication, and without setting
-any other configuration options, you can do so by setting an environment
-variable when creating the container: `NO_AUTHENTICATION=1`. Doing this will
-ignore any configuration file you provide.
-
+any other configuration options, you can do so by using a configuration
+provided in the container for this purpose:
 ```
-docker run -it -p 1883:1883 -e NO_AUTHENTICATION=1 eclipse-mosquitto:<version>
+docker run -it -p 1883:1883 eclipse-mosquitto:<version> mosquitto -c /mosquitto-no-auth.conf
 ```
 
 ## Configuration

docker/2.0/docker-entrypoint.sh

@@ -7,11 +7,4 @@ if [ "$user" = '0' ]; then
 	[ -d "/mosquitto" ] && chown -R mosquitto:mosquitto /mosquitto || true
 fi
 
-if [ "$NO_AUTHENTICATION" = "1" ] && [ "$*" = '/usr/sbin/mosquitto -c /mosquitto/config/mosquitto.conf' ]; then
-	# The user wants to run Mosquitto with no authentication, but without
-	# providing a configuration file. Use the pre-provided file for this.
-	exec /usr/sbin/mosquitto -c /mosquitto-no-auth.conf
-else
-	# Execute whatever command is requested
-	exec "$@"
-fi
+exec "$@"