apply changes to ethers facade

lib/ethers.ex

@@ -564,19 +564,11 @@ defmodule Ethers do
 
   @doc false
   @spec rpc_client() :: atom()
-  def rpc_client, do: Application.get_env(:ethers, :rpc_client, Ethereumex.HttpClient)
+  defdelegate rpc_client(), to: Ethers.RpcClient
 
   @doc false
   @spec get_rpc_client(Keyword.t()) :: {atom(), Keyword.t()}
-  def get_rpc_client(opts) do
-    module =
-      case Keyword.fetch(opts, :rpc_client) do
-        {:ok, module} when is_atom(module) -> module
-        :error -> Ethers.rpc_client()
-      end
-
-    {module, Keyword.get(opts, :rpc_opts, [])}
-  end
+  defdelegate get_rpc_client(opts), to: Ethers.RpcClient
 
   defp pre_process(tx_data, overrides, :call = _action, _opts) do
     {block, overrides} = Keyword.pop(overrides, :block, "latest")
@@ -657,8 +649,8 @@ defmodule Ethers do
     log_params =
       event_filter
       |> EventFilter.to_map(overrides)
-      |> ensure_hex_value(:fromBlock)
-      |> ensure_hex_value(:toBlock)
+      |> ensure_hex_value(:from_block)
+      |> ensure_hex_value(:to_block)
 
     {:ok, log_params}
   end