Add tests for Neo4j 3.1

Author: cheerfulstoic

.travis.yml

@@ -23,7 +23,7 @@ env:
     - NEO4J_URL="http://localhost:7474"
     - NEO4J_BOLT_URL="bolt://localhost:7472"
   matrix:
-    - NEO4J_VERSION=community-3.0.3
+    - NEO4J_VERSION=community-3.1.2
 matrix:
   include:
     - script: "bundle exec rubocop"
@@ -33,6 +33,8 @@ matrix:
       env: "RUBOCOP=true"
 
     # Older versions of Neo4j with latest version of Ruby
+    - rvm: 2.3.1
+      env: NEO4J_VERSION=community-3.0.8
     - rvm: 2.3.1
       env: NEO4J_VERSION=community-2.3.5
     - rvm: 2.3.1
@@ -41,6 +43,8 @@ matrix:
       env: NEO4J_VERSION=community-2.1.8
 
     # Older versions of Neo4j with latest version of jRuby
+    - rvm: jruby-9.0.4.0
+      env: NEO4J_VERSION=community-3.0.8
     - rvm: jruby-9.0.4.0
       env: NEO4J_VERSION=community-2.3.5
     - rvm: jruby-9.0.4.0