Add rust binding client

[CaptainVincent]

Part of #476.

1. Add rust client binding base on EVMC 7.4.0.
2. ~~f8466c7 is a temporary workaround for evmc_host_context cannot be instantiated.~~ cherry-pick b0c40df4f3ced6cac21bd45328334ba1ecd924a6 from #524
3. Update all files' license to Apache 2.0.

I am not yet add any unit test for this module ~~but it work fine with Hera.~~ ~~https://github.com/second-state/rust-ssvm/tree/upgrade-evmc-client~~ ~~Use this branch follow original example section.~~
~~(I add hera as submodule, replace build.rs to build and link libhera.so and update dummy host function in example)~~ but it already applied on https://github.com/second-state/rust-ssvm/tree/evmc-7 could run example with SSVM.

[CaptainVincent]

I saw some ci issues come from my evmc_host_context workaround as below.

1. /home/circleci/project/include/evmc/evmc.h:164:8: error: struct has no members [-Werror=pedantic]
2. error: empty struct is a GNU extension [-Werror,-Wgnu-empty-struct]

struct evmc_host_context {};

3. Code format

-struct evmc_host_context {};
+struct evmc_host_context
+{
+};

4. bindings-go-latest fail reason unknown.

I think I need some suggestions for pass these tests. Thanks.