Update travis go version and golint path

Signed-off-by: Alexander Morozov <[email protected]>

Author: LK4D4

.travis.yml

@@ -1,11 +1,11 @@
 language: go
 sudo: false
 go:
-  - 1.6.1
+  - 1.12.x
   - tip
 install:
   - go get -t ./...
-  - go get github.com/golang/lint/golint
+  - go get golang.org/x/lint/golint
 script:
   - go vet ./...
   - test -z "$(golint ./... | tee /dev/stderr)"