docs: Add basic information about evmc-vmtester

docs/EVMC.md

@@ -16,6 +16,8 @@ to access Ethereum environment and state.
    – a collection of utility functions for easier integration with EVMC.
 - [EVM Instructions](@ref instructions) 
    – the library with collection of metrics for EVM1 instruction set.
+- [EMVC VM Tester](@ref vmtester)
+   – the EVMC-compatibility testing tool for VM implementations.
 
 
 [eWASM]: https://github.com/ewasm/design

docs/VM_Tester.md

@@ -0,0 +1,16 @@
+# EVMC VM Tester {#vmtester}
+
+The EVMC project contains a EVMC-compatibility testing tool for VM implementations.
+
+The tool is called `evmc-vmtester` and to include it in the EVMC build
+add `-DEVMC_TESTING=ON` CMake option to the project configuration step.
+
+Usage is simple as
+
+```sh
+evmc-vmtester [vm]
+```
+
+where `[vm]` is a path to a shared library with VM implementation.
+
+For more information check `evmc-vmtester --help`.