SDK: Add query to chain (or indexer) for current enabled features

[jurevans]

We can query storage keys to determine if a certain features has been enabled on chain:

1. If phase 3 is on, then there should be a storage key corresponding to #<IBC>/mint_limit/<token_address> that will hold a non-zero value. I think if any non-zero mint_limit key exists, then phase 3 has been activated
2. For phase 4, for any token that has the mint_limit key existing with non-zero value, then you can query the key #<Token>/<token_address>/parameters/max_reward_rate. If any key of this kind has non-zero value, then shielded rewards are enabled for that token
3. Phase 5 is simple: there is a boolean in storage with key #<parameters_address>/native_token_transferable