Help debug and mitigate Kusama XCM issue

The new Kusama runtime 1000000 introduced a XCM bug that can result partially executed XCM and stuck of funds.

I worked with Parity devs to debug and identify the root cause of the bug, create a Github issue described action items, a twitter thread explaining the bug, suggestion to parachain teams to workaround the issue. I also created a test script using Chopsticks to reproduce the issue, and use it to verify the fix.

I will also work with Fellowship to setup e2e tests and regression tests for future releases. But this can be considered out of scope of this tip.