Send updated source files to Transifex automatically after success

.travis.yml

@@ -3,4 +3,11 @@ node_js:
   - "4"
   - "6"
   - "7"
-sudo: false
+sudo: required
+after_success:
+  - pip install virtualenv
+  - virtualenv ~/env
+  - source ~/env/bin/activate
+  - pip install transifex-client
+  - sudo echo $'[https://www.transifex.com]\nhostname = https://www.transifex.com\nusername = '"$TRANSIFEX_USER"$'\npassword = '"$TRANSIFEX_PASSWORD"$'\n' > ~/.transifexrc
+  - tx push -s