Make sp_core and sp_runtime dependencies optional, and bump to latest (#760)

* begin porting over traits; remove Config use of Hash

* port over the Header bits that we need

* sp_core_hashing where possible, move Verify to PairSigner, remove unused errors

* tidy up Config things and move related bits into one place

* fix codegen

* copy Era over

* move AccountId, Address, Signer to Signer trait and a pass over fixing examples

* impl MultiAddress, MultiSignature, AccountId32 and add back to Config (for decoding later)

* Copy over StorageKey, StorageData, StorageChangeSet

* subxt core compiling with no sp_core or sp_runtime

* Get examples compiling

* pass over fixing tests

* cargo fmt

* clippy tweaks and update polkadot.rs

* fix codegen docs

* port over special DigestItem encoding/decoding

* clippy and doc fixes

* cargo fmt and example fix

* more cargo fmt-ing...

* substrate-extra to substrate-compat

* cargo.toml comments

* simplify PairSigner trait bounds

* move RPC types to a separate file

* fix docs

* Add some tests for things and other PR feedback

* bump to latest sp deps

* avoid needing substrate-compat feature in a test

codegen/src/api/mod.rs

@@ -169,23 +169,23 @@ impl RuntimeGenerator {
             ),
             (
                 "sp_core::crypto::AccountId32",
-                parse_quote!(#crate_path::ext::sp_core::crypto::AccountId32),
-            ),
-            (
-                "primitive_types::H160",
-                parse_quote!(#crate_path::ext::sp_core::H160),
-            ),
-            (
-                "primitive_types::H256",
-                parse_quote!(#crate_path::ext::sp_core::H256),
-            ),
-            (
-                "primitive_types::H512",
-                parse_quote!(#crate_path::ext::sp_core::H512),
+                parse_quote!(#crate_path::utils::AccountId32),
             ),
             (
                 "sp_runtime::multiaddress::MultiAddress",
-                parse_quote!(#crate_path::ext::sp_runtime::MultiAddress),
+                parse_quote!(#crate_path::utils::MultiAddress),
+            ),
+            (
+                "primitive_types::H160",
+                parse_quote!(#crate_path::utils::H160),
+            ),
+            (
+                "primitive_types::H256",
+                parse_quote!(#crate_path::utils::H256),
+            ),
+            (
+                "primitive_types::H512",
+                parse_quote!(#crate_path::utils::H512),
             ),
             (
                 "frame_support::traits::misc::WrapperKeepOpaque",