Support Android 6/SDK v23

[tlvince]

Currently the minimum supported SDK is Android 8/SDK v26. Regrettably, there are a lot of devices (e.g. Frameo photo frames, old tablets) suitable for kiosk that run on older versions of Android.

Fully Kiosk currently supports Android 5, but will soon be moving to min Android 6. Could webview-kiosk support Android 6?

[nktnet1]

I've added support for Android 5.0 (Lollipop, Sdk 21) in this pull request:

• feat: support android 5.0 - lollipop (minSdk = 21) #11

Released in v0.17.1.

[tlvince]

Thanks!