add readme

Author: cassc

README.md

@@ -0,0 +1,25 @@
+# Benchmark Rust EVM
+
+To run the benchmark, 
+
+``` bash
+cargo run --release
+```
+
+It will 
+* First deploy a compiled ERC20 contract
+* Get the address of the deployed contract
+* Execute a transfer call method from the contract by microbenchmark for 30secs
+* Call the same method for 100_000 times
+
+
+Sample results:
+
+``` text
+================================================================================
+EXECUTE contract deploy
+RETURNS Exit((Succeed(Returned), Some(0xc15d2ba57d126e6603240e89437efd419ce329d2), []))
+Contract deployed to adderss Some(0xc15d2ba57d126e6603240e89437efd419ce329d2)
+execute_contract_method (30.2s) ...      20_697.744 ns/iter (0.991 R²)
+100000 runs, total 2043ms, average: 0.02043ms
+```