Travis CI: also build with vendored dependencies

.travis.yml

@@ -23,6 +23,11 @@ script:
   - ./gocryptfs -speed
   - ./test.bash
   - ./crossbuild.bash
+  - echo "rebuild with locked dependencies"
+  - wget https://github.com/golang/dep/releases/download/v0.3.2/dep-linux-amd64 -O dep
+  - chmod +x dep
+  - ./dep ensure
+  - ./build.bash
 
 # fuse on travis
 sudo: required