Add Accessibility

[lsurvila]

Could be separate or in different categories

Maybe part of Design Guides branch:
https://material.io/design/usability/accessibility.html#understanding-accessibility

Semantics in Compose branch:
https://developer.android.com/jetpack/compose/semantics

Accessibility Scanner could go in Testing branch:
https://play.google.com/store/apps/details?id=com.google.android.apps.accessibility.auditor