message: Improve formatting of README
diff: @@ -111,7 +111,7 @@ cd build # or wherever you ran CMake before
  cmake -DBOND_ENABLE_GRPC=TRUE -DgRPC_ZLIB_PROVIDER=package ..
  ```
  -Running the following command in the build directory will build and execute all
  +Running the following command in the `build` directory will build and execute all
  the tests and examples:
  ```bash
  @@ -156,7 +156,7 @@ cmake -DBOND_ENABLE_GRPC=FALSE -G Xcode ..
  ```
  You can build and run unit tests by building the `check` target in Xcode or by
  -running make in the build directory:
  +running make in the `build` directory:
  ```bash
  make --jobs 8 check
  