message: Make WAT purely S-expressions
diff: (then
  (i64.store (get_local $t) (i64.add (i64.load (get_local $t)) (i64.extend_u/i32 (get_local $i))))
  (set_local $i (i32.const 0))
  - get_local $ctx
  - call $blake2b_compress
  +
  + (call $blake2b_compress (get_local $ctx))
  )
  )
  ;; ctx.c = i (for good meassure)
  (i64.store (get_local $c) (i64.extend_u/i32 (get_local $i)))
  - get_local $ctx
  - call $blake2b_compress
  + (call $blake2b_compress (get_local $ctx))
  )
  (func $blake2b_compress (export "blake2b_compress") (param $ctx i32)
  