message: Add the cosmwasm-* version changes to MIGRATING.md
diff: @@ -6,6 +6,20 @@ major releases of `cosmwasm`. Note that you can also view the
  ## 0.15 -> 0.16 (unreleased)
  +- Update CosmWasm dependencies in Cargo.toml (skip the ones you don't use):
  +
  + ```
  + [dependencies]
  + cosmwasm-std = "0.16.0"
  + cosmwasm-storage = "0.16.0"
  + # ...
  +
  + [dev-dependencies]
  + cosmwasm-schema = "0.16.0"
  + cosmwasm-vm = "0.16.0"
  + # ...
  + ```
  +
  - The `attr` function now accepts arguments that implement `Into<String>` rather
  than `ToString`. This means that "stringly" types like `&str` are still
  accepted, but others (like numbers or booleans) have to be explicitly
  @@ -176,6 +190,20 @@ major releases of `cosmwasm`. Note that you can also view the
  ## 0.14 -> 0.15
  +- Update CosmWasm dependencies in Cargo.toml (skip the ones you don't use):
  +
  + ```
  + [dependencies]
  + cosmwasm-std = "0.15.0"
  + cosmwasm-storage = "0.15.0"
  + # ...
  +
  + [dev-dependencies]
  + cosmwasm-schema = "0.15.0"
  + cosmwasm-vm = "0.15.0"
  + # ...
  + ```
  +
  - Combine `messages` and `submessages` on the `Response` object. The new format
  uses `messages: Vec<SubMsg<T>>`, so copy `submessages` content, and wrap old
  messages using `SubMsg::new`. Here is how to change messages:
  