* update substrate

* fix tests

* Add dust removal and transfer_all in orml-tokens.

* Ensure existential rule for transfer, deposit and withdraw.

* orml-tokens transfer: return error if dest balance is zero and transfer amount below existential deposit.

* set_balance helper.

* Existential deposit unit tests.

* Fix orml-currencies mock.

* Renaming.

* Update transfer_all in orml-tokens.

* rename to FRAME

* fix test

* Rename paint to palette.

* Fix typo.

* Update comments.

* Update paint balance adapting.

* Update error type.

* Update multi currency to basic currency adapting.

* Remove HasCompact bound for CurrencyId.

* Update BasicCurrencyAdapter struct define.

* rename srml to paint

* fix case

* Update slash: return gap instead of slashed amount.

* Add unit test for tokens module slash.

* Tokens module: impl MultiCurrencyExtended.

* Minor fixes.

* Error type for MultiCurrency trait and tokens module.

* fmt

* Update error type.

* Update transfer unit test.

* Tokens module unit tests.

* Remove workspace src directory

* Add example crate.

* fmt

* Update example.

* Minor fixes.

* Remove allow dead code.

* Define MultiCurrency trait.

* Declare storage.

* Impl multi currency trait for tokens module.

* Balance transfer.

* Fix typo.

* fmt

* Add transferred event.

* Update tokens trait and slash impl.

* Use value type for currency id params.

* fmt