Asset Conversion release to westmint (#2148)

* Dex and payment by dex in westmint

* Wrap U256 type for now

(to support required traits.)

* cargo fmt

* We can now use U256

* Rename PromotedBalance

* name change

* Updating the code to master.

TODO: handle dust!

* cargo fmt

* Minimising changes and step towards getting benchmarks compiling

(still a From<u32> bound in the pallet)

* minimise diff

* Update parachains/runtimes/assets/westmint/src/lib.rs

Co-authored-by: Jegor Sidorenko <5252494+jsidorenko@users.noreply.github.com>

* Update parachains/runtimes/assets/westmint/src/lib.rs

Co-authored-by: Jegor Sidorenko <5252494+jsidorenko@users.noreply.github.com>

* Update parachains/common/src/impls.rs

Co-authored-by: Jegor Sidorenko <5252494+jsidorenko@users.noreply.github.com>

* Fix benchmark build

* Add in AssetConversionAPI

* Handle dust

* cargo fmt

* Don't need to be explicit that it's AccountId32

* remove pool setup fee

(Asset deposit fees are a sufficient anti-spam measure)

* More natural way to specify native

* cargo fmt

* Update parachains/runtimes/assets/westmint/src/lib.rs

* Additional required impls

* either form of multilocation should be acceptable.

* add call filter exclusion

* Fix typo & try_convert now fails if native is converted

* merge master fixup

* Fix: HoldReason should be there.

* Box MultiAssetId

Otherwise it blows out the Call enum memory size.

* cargo fmt

* update lock file

* add std feature, update lock file

* need to turn on std on common

* adding in westmint tests

* WeightToFee must be from the destination chain.

* cargo fmt

* account for higher ED on westmint

* type removed as not used

* cargo fmt

* remove unused import

* minimising diff

* import needed only with feature enabled

* use multilocation contains

* move the impls to separate file

* simplify on conversion

* simplify on reverse conversion also.

* rename var

* clippy

* removed dead code

* cargo fmt

* Use pay by swap

* review suggestions

* cargo fmt

* Update parachains/runtimes/assets/asset-hub-westend/src/lib.rs

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

* add benchmarks for new assets pallet

* revert common/src changes

* need a concrete id

* more fixes

* lock

---------

Co-authored-by: Jegor Sidorenko <5252494+jsidorenko@users.noreply.github.com>
Co-authored-by: joepetrowski <joe@parity.io>
Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

cumulus/parachains/runtimes/assets/common/src/runtime_api.rs

@@ -17,8 +17,8 @@
 
 use codec::{Codec, Decode, Encode};
 use frame_support::RuntimeDebug;
-use sp_std::vec::Vec;
-use xcm::latest::MultiAsset;
+#[cfg(feature = "std")]
+use {sp_std::vec::Vec, xcm::latest::MultiAsset};
 
 /// The possible errors that can happen querying the storage of assets.
 #[derive(Eq, PartialEq, Encode, Decode, RuntimeDebug, scale_info::TypeInfo)]