- use Mobile-Detect@2.8.12
    - breaking change: phone() and tablet() won't return 'UnknownMobile' -> have to check mobile() as well (issue #20)
    - breaking change: fallback detection phone/tablet is now based on smaller screen side (issue #23)
    - expose internal implementation in case somebody wants to quick fix or monkey-patch the behaviour
    - add demo page for gh-pages
    - tweak jshint