Use the generated DispatchError instead of the hardcoded Substrate one (#394)

* WIP DispatchError generic param

* main crate now compiling with new E generic param for DispatchError

* Remove E param from RpcClient since it doesn't really need it

* Point to generated DispatchError in codegen so no need for additional param there

* More error hunting; cargo check --all-targets passes now

* Use our own RuntimeVersion struct (for now) to avoid error decoding into sp_version::RuntimeVersion

* cargo fmt

* fix docs and expose private documented thing that I think should be pub

* move error info to compile time so that we can make DispatchError a little nicer to work with

* cargo fmt

* clippy

* Rework error handling to remove <E> param in most cases

* fix Error doc ambiguity (hopefully)

* doc tweaks

* docs: remove dismbiguation thing that isn't needed now

* One more Error<E> that can be a BasicError

* rewrite pallet errors thing into normal loops to tidy

* tidy errors codegen a little

* tidy examples/custom_type_derives.rs a little

* cargo fmt

* silcnce clippy in example

tests/integration/frame/contracts.rs

@@ -25,6 +25,7 @@ use crate::{
         },
         system,
         DefaultAccountData,
+        DispatchError,
     },
     test_context,
     NodeRuntimeSignedExtra,
@@ -67,7 +68,9 @@ impl ContractsTestContext {
         self.cxt.api.tx().contracts()
     }
 
-    async fn instantiate_with_code(&self) -> Result<(Hash, AccountId), Error> {
+    async fn instantiate_with_code(
+        &self,
+    ) -> Result<(Hash, AccountId), Error<DispatchError>> {
         log::info!("instantiate_with_code:");
         const CONTRACT: &str = r#"
                 (module
@@ -118,7 +121,7 @@ impl ContractsTestContext {
         code_hash: Hash,
         data: Vec<u8>,
         salt: Vec<u8>,
-    ) -> Result<AccountId, Error> {
+    ) -> Result<AccountId, Error<DispatchError>> {
         // call instantiate extrinsic
         let result = self
             .contracts_tx()
@@ -147,7 +150,8 @@ impl ContractsTestContext {
         &self,
         contract: AccountId,
         input_data: Vec<u8>,
-    ) -> Result<TransactionProgress<'_, DefaultConfig>, Error> {
+    ) -> Result<TransactionProgress<'_, DefaultConfig, DispatchError>, Error<DispatchError>>
+    {
         log::info!("call: {:?}", contract);
         let result = self
             .contracts_tx()