Use `page.excerpt` if available for the page description.
We now support 35 languages
 - Thai was added in mpc-hc/mpc-hc@0bab09a7a7
 - Arabic was added in mpc-hc/mpc-hc@be99091d18
Update dependencies.
README.md: use master branch for Travis badge.
Tweak alerts.

Add a dismissible alert for the browser case.

Many thanks to @hnrch02 for his awesome snippet to save the dismissible alerts' state!
Merge pull request #43 from mpc-hc/alerts

Tweak alerts.
Update dependencies.
Minor wording tweaks.
Tweak mobile view.
Add a dropdown navbar menu and icons.
More tweaks for thumbs.