Change test matrix in .travis.yml (brianc#1002)

* Change test matrix in .travis.yml

Add tests for node @ v6. Remove node & postgres test permutations for older versions of node.

* Remove sub-versions

* Remove minor version from node 4

Author: brianc

.travis.yml

@@ -14,39 +14,27 @@ addons:
 
 matrix:
   include:
-    - node_js: "0.10"
-      addons:
-        postgresql: "9.1"
-    - node_js: "0.10"
-      addons:
-        postgresql: "9.2"
-    - node_js: "0.10"
-      addons:
-        postgresql: "9.3"
     - node_js: "0.10"
       addons:
         postgresql: "9.4"
     - node_js: "0.12"
       addons:
-        postgresql: "9.1"
-    - node_js: "0.12"
-      addons:
-        postgresql: "9.2"
-    - node_js: "0.12"
+        postgresql: "9.4"
+    - node_js: "4"
       addons:
-        postgresql: "9.3"
-    - node_js: "0.12"
+        postgresql: "9.4"
+    - node_js: "5"
       addons:
         postgresql: "9.4"
-    - node_js: "4.1"
+    - node_js: "6"
       addons:
         postgresql: "9.1"
-    - node_js: "4.1"
+    - node_js: "6"
       addons:
         postgresql: "9.2"
-    - node_js: "4.1"
+    - node_js: "6"
       addons:
         postgresql: "9.3"
-    - node_js: "4.1"
+    - node_js: "6"
       addons:
         postgresql: "9.4"