Add Dex pallet (#407)

* Move pallet-asset-conversion

* update licensing

* initial integration

* Integrate Currency & Assets types

* integrate liquidity tokens

* fmt

* integrate dex pallet tests

* fmt

* compilation error fixes

* integrate dex benchmarks

* fmt

* cargo clippy

* replace all occurrences of "asset" with "coin"

* add the actual add liq/swap logic to in-instructions

* add client side & tests

* fix deny

* Lint and changes

- Renames InInstruction::AddLiquidity to InInstruction::SwapAndAddLiquidity
- Makes create_pool an internal function
- Makes dex-pallet exclusively create pools against a native coin
- Removes various fees
- Adds new crates to GH workflow

* Fix rebase artifacts

* Correct other rebase artifact

* Correct CI specification for liquidity-tokens

* Correct primitives' test to the standardized pallet account scheme

---------

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>

substrate/in-instructions/primitives/src/shorthand.rs

@@ -26,7 +26,7 @@ pub enum Shorthand {
     minimum: Amount,
     out: OutInstruction,
   },
-  AddLiquidity {
+  SwapAndAddLiquidity {
     origin: Option<ExternalAddress>,
     minimum: Amount,
     gas: Amount,
@@ -47,7 +47,7 @@ impl TryFrom<Shorthand> for RefundableInInstruction {
     Ok(match shorthand {
       Shorthand::Raw(instruction) => instruction,
       Shorthand::Swap { .. } => todo!(),
-      Shorthand::AddLiquidity { .. } => todo!(),
+      Shorthand::SwapAndAddLiquidity { .. } => todo!(),
     })
   }
 }