Bump travis Go version to 1.8

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>

.travis.yml

@@ -10,7 +10,7 @@ os:
 language: go
 
 go:
-    - 1.7
+    - 1.8
 
 env:
   - TEST_NO_FUSE=1 TEST_VERBOSE=1 TEST_SUITE=test_go_expensive

ci/Dockerfile.buildenv

-FROM golang:1.7
+FROM golang:1.8
 MAINTAINER Jakub Sztandera <kubuxu@ipfs.io>