Update travis to include latest released versions

Author: msmygit

.travis.yml

@@ -28,11 +28,13 @@ env:
     - TEST_PARALLEL_TASKS=1 #Times out on 2
 
   jobs:
-    - CCM_CASSANDRA_VERSION=3.11.6
+    - CCM_CASSANDRA_VERSION=3.11.9
     - CCM_CASSANDRA_VERSION=3.0.20
+    - CCM_CASSANDRA_VERSION=4.0-beta4
     - CCM_CASSANDRA_VERSION=2.1.21
-    - CCM_CASSANDRA_VERSION=6.0.11 CCM_IS_DSE=true DSE_VERSION=6.0.11 CCM_SERVER_TYPE=dse
-    - CCM_CASSANDRA_VERSION=6.8.5  CCM_IS_DSE=true DSE_VERSION=6.8.5 CCM_SERVER_TYPE=dse
+    - CCM_CASSANDRA_VERSION=6.0.14 CCM_IS_DSE=true DSE_VERSION=6.0.14 CCM_SERVER_TYPE=dse
+    - CCM_CASSANDRA_VERSION=6.7.12 CCM_IS_DSE=true DSE_VERSION=6.7.12 CCM_SERVER_TYPE=dse
+    - CCM_CASSANDRA_VERSION=6.8.9 CCM_IS_DSE=true DSE_VERSION=6.8.9 CCM_SERVER_TYPE=dse
 
 install:
   - pip install --user ccm