Update encrypted npm and rubygem auth secrets

Update the `npmrc` file to use the NPM v2+ auth format. See:
https://docs.travis-ci.com/user/deployment/npm/

The NPM 2+ format looks like:
```
//registry.npmjs.org/:_authToken=XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
```

The rubygems auth/API key should not have changed.

config.sh

@@ -9,7 +9,7 @@ git config --global user.name "Travis CI"
 git config --global user.email "[email protected]"
 
 # This openssl command was generated automatically by `travis encrypt-file`, see `.travis/README.md` for more details
-openssl aes-256-cbc -K $encrypted_df4ab1bff570_key -iv $encrypted_df4ab1bff570_iv -in .travis/secrets.tar.enc -out .travis/secrets.tar -d
+openssl aes-256-cbc -K $encrypted_ed23d39ae37d_key -iv $encrypted_ed23d39ae37d_iv -in .travis/secrets.tar.enc -out .travis/secrets.tar -d
 
 tar xvf .travis/secrets.tar
 mkdir -p ~/.gem/