Vaccination server - ValueSet, Responses,.. (EXPOSUREAPP-6855) (#3141)

* Created vaccination server

* Separation of concern

* Lazy initialization

* better err messages

* Local caching

* detekt & ktlint clean

* missing import

* Update DataResetTest.kt

* whatever

* Fixed tests

* Serialize as we want

* - Load value sets, Use download cdn http client

* 304 cleanup

* Created stored value set version

* fix conflicted VaccinationListFragment

* clean detekt & sourceCheck

* Update VaccinationListViewModel.kt

* user errors wont crash the app

* Tests for repo

* clean

* Ignore server cache headers

* detekt

Co-authored-by: Matthias Urhahn <matthias.urhahn@sap.com>