Fix.email typhoon copy

[jannisvisser]

Describe your changes

Resolves issue 908

Checklist before requesting a review

• I have performed a self-review of my code
• I have added tests wherever relevant
• I have made sure that all automated checks pass before requesting a review

Notes for the reviewer

1. I went for a pretty blunt overwriting of the generic ux copy in case of typhoon for now. But otherwise it got even more confusing, mixing up partly generic with partly specific code.
2. Added new API-tests per typhoon scenario.
3. Note that the mock sccenarios / API-tests do not cover all possible scenarios. E.g. all the noLandfall/noLandfallYet/afterLandfall are all trigger (not warning). Also the afterLandfall event is landfall (not no-landfall). So maybe check for those cases extra carefully. (Maybe document in code which cases are covered in mock/api and which not?)

[jannisvisser]

@gulfaraz just FYI'ing so you're aware.

[gulfaraz]

Looks good @jannisvisser. It's nice that you also added tests for these changes.