Add some missing properties in env variables (#574)

server.properties

@@ -37,3 +37,15 @@ motd=A Minecraft Server powered by Docker
 generator-settings=
 rcon.password=
 max-world-size=29999984
+broadcast-console-to-ops=true
+broadcast-rcon-to-ops=true
+enable-jmx-monitoring=false
+sync-chunk-writes=true
+enable-status=true
+entity-broadcast-range-percentage=100
+function-permission-level=2
+network-compression-threshold=256
+op-permission-level=4
+prevent-proxy-connections=false
+use-native-transport=true
+enforce-whitelist=false