modify travis.yml

Author: cg33

.travis.yml

@@ -17,6 +17,7 @@ before_script:
   - go get github.com/NebulousLabs/fastrand
   - go get github.com/gin-gonic/gin
   - go get golang.org/x/text/language
+  - go get github.com/gavv/httpexpect
 
 script:
   - cd /home/travis/gopath/src/github.com/chenhg5/go-admin && make deps