[Doc]Reorder options for kafka input (logstash-plugins#31)

docs/input-kafka.asciidoc

@@ -81,6 +81,7 @@ NOTE: Some of these options map to a Kafka option. See the https://kafka.apache.
 | <<plugins-{type}s-{plugin}-bootstrap_servers>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-check_crcs>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-client_id>> |<<string,string>>|No
+| <<plugins-{type}s-{plugin}-client_rack>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-connections_max_idle_ms>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-consumer_threads>> |<<number,number>>|No
 | <<plugins-{type}s-{plugin}-decorate_events>> |<<boolean,boolean>>|No
@@ -121,7 +122,6 @@ NOTE: Some of these options map to a Kafka option. See the https://kafka.apache.
 | <<plugins-{type}s-{plugin}-topics>> |<<array,array>>|No
 | <<plugins-{type}s-{plugin}-topics_pattern>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-value_deserializer_class>> |<<string,string>>|No
-| <<plugins-{type}s-{plugin}-client_rack>> |<<string,string>>|No
 |=======================================================================
 
 Also see <<plugins-{type}s-{plugin}-common-options>> for a list of options supported by all
@@ -182,6 +182,19 @@ The id string to pass to the server when making requests. The purpose of this
 is to be able to track the source of requests beyond just ip/port by allowing
 a logical application name to be included.
 
+[id="plugins-{type}s-{plugin}-client_rack"]
+===== `client_rack` 
+
+  * Value type is <<string,string>>
+  * There is no default value for this setting.
+
+A rack identifier for the Kafka consumer. 
+Used to select the physically closest rack for the consumer to read from.
+The setting corresponds with Kafka's `broker.rack` configuration.
+
+NOTE: Available only for Kafka 2.4.0 and higher. See
+https://cwiki.apache.org/confluence/display/KAFKA/KIP-392%3A+Allow+consumers+to+fetch+from+closest+replica[KIP-392].
+
 [id="plugins-{type}s-{plugin}-connections_max_idle_ms"]
 ===== `connections_max_idle_ms` 
 
@@ -583,19 +596,6 @@ The topics configuration will be ignored when using this configuration.
 
 Java Class used to deserialize the record's value
 
-
-[id="plugins-{type}s-{plugin}-client_rack"]
-===== `client_rack` 
-
-  * Value type is <<string,string>>
-  * There is no default value for this setting.
-
-A rack identifier for the Kafka consumer. 
-Used to select the physically closest rack for the consumer to read from.
-The setting corresponds with Kafka's `broker.rack` configuration.
-
-NOTE: Only available for Kafka 2.4.0 and higher; see https://cwiki.apache.org/confluence/display/KAFKA/KIP-392%3A+Allow+consumers+to+fetch+from+closest+replica[KIP-392].
-
 [id="plugins-{type}s-{plugin}-common-options"]
 include::{include_path}/{type}.asciidoc[]