Fix/wercker (matcornic#178)

fix fail of CI matcornic#176

wercker.yml

@@ -1,16 +1,14 @@
 box: golang
 build:
   steps:
-    # Sets the go workspace and places you package
-    # at the right place in the workspace tree
-    - setup-go-workspace
-
     # Gets the dependencies
     - script:
         name: get hugo
         code: |
-          go get github.com/gohugoio/hugo
-
+          git clone https://github.com/gohugoio/hugo.git && cd hugo && go install
+    # Sets the go workspace and places you package
+    # at the right place in the workspace tree
+    - setup-go-workspace
     # Build the project
     - script:
         name: build site