Specify point versions in Travis
diff --git a/.travis.yml b/.travis.yml
index eeaf72b..86b428f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,10 +2,10 @@
 script: "./test.sh"
 sudo: false
 go:
-    - 1.2
-    - 1.3
-    - 1.4.1
-    - 1.5
+    - 1.2.2
+    - 1.3.3
+    - 1.4.2
+    - 1.5.1
     - tip
 before_install:
   - go get github.com/axw/gocov/gocov