Test on 1.5; remove 1.2 tests

.travis.yml

@@ -1,8 +1,8 @@
 language: go
 go:
-  - 1.2
   - 1.3
   - 1.4
+  - 1.5
   - tip
 before_install:
   - sudo apt-get install libgeoip-dev bzr