ICS 28: WASM Client (#571)

* add 028 wasm client

* Accepting suggestion

Co-authored-by: Christopher Goes <cwgoes@pluranimity.org>

* use WASM everywhere

* Accepting suggestion

Co-authored-by: Christopher Goes <cwgoes@pluranimity.org>

* replace WASM with Wasm

* update data structures

* allow light client to update its own consensus/client state

* rename ics-028-wasm-client ics-008-wasm-client

* remove proof verification on the Go side

* rename epoch{number,height} to revision{number, height}

* rephrase misbehaviour description

* apply @AdityaSripal feedback

Co-authored-by: Christopher Goes <cwgoes@pluranimity.org>
Co-authored-by: Kaczanowski Mateusz <kaczanowski.mateusz@gmail.com>