Upgrade to cosmwasm 1.0.0-soon

[ethanfrey]

Closes #427

I fixed the compile errors (even if I wish to do this better in the helpers later), but the tests fail for odd reasons. For example, try cargo test in cw1-whitelist. I get:

error[E0308]: mismatched types
  --> contracts/cw1-whitelist/src/integration_tests.rs:17:19
   |
17 |     App::new(api, env.block, bank, storage)
   |                   ^^^^^^^^^ expected struct `cosmwasm_std::types::BlockInfo`, found struct `BlockInfo`
   |
   = note: perhaps two different versions of crate `cosmwasm_std` are being used?

Quite confused here, as these are aliases (cosmwasm_std::BlockInfo and cosmwasm_std::types::BlockInfo) and I did check that Cargo.toml is updated to 1.0.0-soon.

I'd be happy if anyone can investigate (and fix)