Revert "travis fold env"

This reverts commit 4a12632364.

.travis.yml

       osx_image: xcode9
       language: objective-c
       before_install:
-        - ./scripts/travis-fold.sh "source ./scripts/env/env.ios.sh"
+        - source ./scripts/env/env.ios.sh
       script:
         - ./scripts/travis-fold.sh "npm run test-unit-ios -- --release"
         - ./scripts/travis-fold.sh "npm run test-e2e-ios -- --release"
       jdk: oraclejdk8
       language: java
       before_install:
-        - ./scripts/travis-fold.sh "source ./scripts/env/env.android.sh"
+        - source ./scripts/env/env.android.sh
       script:
         - ./scripts/travis-fold.sh "npm run test-unit-android -- --release"
         - ./scripts/travis-fold.sh "npm run test-e2e-android -- --release"
   - v2
 
 install:
-  - ./scripts/travis-fold.sh "nvm install 8"
+  - nvm install 8
   - ./scripts/travis-fold.sh "npm install"
   - ./scripts/travis-fold.sh "npm run clean"