Flutter Integration support for Target on Mobile

We have more and more customer using the Fluter Development Platform for their Mobile Apps. 

The lack of OOTB supported integration is a blocker to adoption of Target on Mobile and even a deterrer for using Target company wide (as most companies would want to use the same optimisation solution across all their channels - web, mobile, emails, etc.

We either need a well documented way of customising the existing SDK to allow for the integration between Target and Flutter or a supported way of integrating the two.