implement Router.sol and associated functions (#92)

* start Router contract

* use calldata for function args

* var name changes

* start testing router contract

* test with and without abi.encode

* cleanup

* why tf isn't tests/utils working

* cleanup tests

* remove unused files

* wip

* fix router contract and tests, add set/update public keys funcs

* impl some Froms

* make execute non-reentrant

* cleanup

* update Router to use ReentrancyGuard

* update contract to use errors, use bitfield in Executed event, minor other fixes

* wip

* fix build issues from merge, tests ok

* Router.sol cleanup

* cleanup, uncomment stuff

* bump ethers.rs version to latest

* make contract functions take generic middleware

* update build script to assert no compiler errors

* hardcode pubkey parity into contract, update tests

* Polish coins/ethereum in various ways

---------

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

coins/ethereum/src/abi/mod.rs

@@ -0,0 +1,6 @@
+#[rustfmt::skip]
+#[allow(clippy::all)]
+pub(crate) mod schnorr;
+#[rustfmt::skip]
+#[allow(clippy::all)]
+pub(crate) mod router;