fix travis documentation upload

.travis.yml

@@ -1,10 +1,8 @@
 dist: trusty
 sudo: required
-
 language:
 - rust
 - cpp
-
 addons:
   apt:
     sources:
@@ -13,17 +11,20 @@ addons:
     - gcc-6
     - g++-6
     - cmake
-
 script:
 - export CC=/usr/bin/gcc-6
 - export CXX=/usr/bin/g++-6
 - cargo build --release --verbose
 - cargo test --release --verbose
 - cargo test --release --manifest-path=spec/Cargo.toml
-  
-after_success: |
+after_success: |-
+  [ $TRAVIS_BRANCH = master ] &&
+  [ $TRAVIS_PULL_REQUEST = false ] &&
   cargo doc \
   && echo '<meta http-equiv=refresh content=0;url=parity_wasm/index.html>' > target/doc/index.html && \
   sudo pip install ghp-import && \
   ghp-import -n target/doc && \
   git push -qf https://${TOKEN}@github.com/${TRAVIS_REPO_SLUG}.git gh-pages
+env:
+  global:
+    secure: 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