build: Fix Travis vet issues (hashicorp#14010)

* Use latest in go 1.8 branch for travis

* Fix ongoing vet issues
Move vet step after the testing step in travis
Correct Makefile vet step to check correct files

.travis.yml

@@ -2,7 +2,7 @@ dist: trusty
 sudo: false
 language: go
 go:
-- 1.8
+- 1.8.x
 
 # add TF_CONSUL_TEST=1 to run consul tests
 # they were causing timouts in travis
@@ -25,7 +25,7 @@ install:
 - bash scripts/gogetcookie.sh
 - go get github.com/kardianos/govendor
 script:
-- make vet vendor-status test
+- make vendor-status test vet
 - GOOS=windows go build
 branches:
   only:

Makefile

@@ -75,8 +75,8 @@ cover:
 # vet runs the Go source code static analysis tool `vet` to find
 # any common errors.
 vet:
-	@echo "go vet ."
-	@go vet $$(go list ./... | grep -v vendor/) ; if [ $$? -eq 1 ]; then \
+	@echo 'go vet $$(go list ./... | grep -v /terraform/vendor/)'
+	@go vet $$(go list ./... | grep -v /terraform/vendor/) ; if [ $$? -eq 1 ]; then \
 		echo ""; \
 		echo "Vet found suspicious constructs. Please check the reported constructs"; \
 		echo "and fix them if necessary before submitting the code for review."; \