Add the 'Device Trust Checks' guide as seen in the structure (https://docs.google.com/document/d/1vT9LjMyGYIiBu6w8xUnWQ6eISvGHFXx_aqetZrp7M1I/edit). Existing docs can be found in thd SDKs, e.g. https://github.com/aerogear/aerogear-android-sdk/blob/master/docs/modules/ROOT/pages/using-security-sdk.adoc

This should be written with code examples for all platforms.