fixing nvm

.travis.yml

@@ -33,8 +33,9 @@ before_install:
   - set -e
   - brew update
   - brew cask install java
-  - touch ~/.bash_profile
-  - curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash
+  - rm -rf ~/.nvm
+  - git clone https://github.com/creationix/nvm.git ~/.nvm
+  - source ~/.nvm/nvm.sh
   - nvm install $NODE_VERSION
   - curl -o- -L https://yarnpkg.com/install.sh | bash