Update libssn3 via .travis.yml
Update libssn3 via .travis.yml

References #33.

GoogleChrome/puppeteer,GoogleChrome/puppeteer,ianchn/puppeteer,GoogleChrome/puppeteer,puppeteer/puppeteer,ianchn/puppeteer,brutalcrozt/puppeteer,michaelfward/puppeteer,elisherer/puppeteer,brutalcrozt/puppeteer,a1ph/puppeteer,puppeteer/puppeteer,elisherer/puppeteer,michaelfward/puppeteer,a1ph/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer