Add vendor check now that content is vendored

Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com>

.travis.yml

@@ -1,24 +1,24 @@
 language: go
 go:
-  - "1.10.x"
-  - "1.11.x"
+  - "1.12.x"
+  - "1.13.x"
 
 go_import_path: github.com/containerd/console
 
+env:
+  - GO111MODULE=on
+
 install:
-  - go get -d
-  - GOOS=openbsd go get -d
-  - GOOS=solaris go get -d
-  - GOOS=windows go get -d
-  - go get -u github.com/vbatts/git-validation
-  - go get -u github.com/kunalkushwaha/ltag
+  - pushd ..; go get -u github.com/vbatts/git-validation; popd
+  - pushd ..; go get -u github.com/kunalkushwaha/ltag; popd
 
 before_script:
   - pushd ..; git clone https://github.com/containerd/project; popd
 
 script:
   - DCO_VERBOSITY=-q ../project/script/validate/dco
   - ../project/script/validate/fileheader ../project/
+  - travis_wait ../project/script/validate/vendor
   - go test -race
   - GOOS=openbsd go build
   - GOOS=openbsd go test -c

go.sum

@@ -1,3 +1,4 @@
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 golang.org/x/sys v0.0.0-20191120155948-bd437916bb0e h1:N7DeIrjYszNmSW409R3frPPwglRwMkXSBzwVbkOjLLA=
 golang.org/x/sys v0.0.0-20191120155948-bd437916bb0e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=