Run Linux CI with sudo and increase inotify limit

Author: emmax86

.travis.yml

@@ -1,3 +1,5 @@
+sudo: true
+
 env:
   matrix:
     - export NODE_VERSION="6" CC=clang CXX=clang++ npm_config_clang=1
@@ -14,6 +16,7 @@ git:
 compiler: clang
 
 before_install:
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p; fi
   - git clone https://github.com/creationix/nvm.git ./.nvm
   - source ./.nvm/nvm.sh
   - nvm install $NODE_VERSION