message: Changed rustup toolchain version (all test passed)
diff: @@ -32,10 +32,10 @@ curl https://sh.rustup.rs -sSf | sh
  Rust nightly is required to build this project.
  ```
  -rustup install nightly-2019-07-30
  -rustup default nightly-2019-07-30
  +rustup install nightly-2019-08-13
  +rustup default nightly-2019-08-13
  ```
  -Application has been tested to compile with `rustc 1.38.0-nightly (dddb7fca0 2019-07-30)`.
  +Application has been tested to compile with `rustc 1.38.0-nightly (60960a260 2019-08-12)`.
  **3. Install OCaml**
  