Account design

[Art3miX]

Our current account implementation is a basic version of what we want from the account to do, it was build mainly to work with the rebalancer as a service, and probably is good to work with any rebalancer-like service in the future.

But we want the account to be much more then that, and we need to make sure that the account design is finalized ASAP in order to prevent any future migrations that will always be a pain to do because the nature of the account is to be controlled by the user and not directly by us (in most cases) meaning we need to keep account versioning as well.

Need to address:

• - Valence account have a "trustee" build in with permissions? #3