Test against more recent versions

.travis.yml

@@ -1,6 +1,5 @@
 language: go
 go:
-- 1.9.x
 - 1.10.x
 - 1.11.x
 
@@ -12,9 +11,9 @@ env:
   - KAFKA_HOSTNAME=localhost
   - DEBUG=true
   matrix:
-  - KAFKA_VERSION=1.0.0
-  - KAFKA_VERSION=1.1.0
-  - KAFKA_VERSION=2.0.0
+  - KAFKA_VERSION=1.1.1
+  - KAFKA_VERSION=2.0.1
+  - KAFKA_VERSION=2.1.0
 
 before_install:
 - export REPOSITORY_ROOT=${TRAVIS_BUILD_DIR}

utils.go

@@ -156,6 +156,7 @@ var (
 	V1_0_0_0  = newKafkaVersion(1, 0, 0, 0)
 	V1_1_0_0  = newKafkaVersion(1, 1, 0, 0)
 	V2_0_0_0  = newKafkaVersion(2, 0, 0, 0)
+	V2_1_0_0  = newKafkaVersion(2, 1, 0, 0)
 
 	SupportedVersions = []KafkaVersion{
 		V0_8_2_0,
@@ -175,9 +176,10 @@ var (
 		V1_0_0_0,
 		V1_1_0_0,
 		V2_0_0_0,
+		V2_1_0_0,
 	}
 	MinVersion = V0_8_2_0
-	MaxVersion = V2_0_0_0
+	MaxVersion = V2_1_0_0
 )
 
 func ParseKafkaVersion(s string) (KafkaVersion, error) {