Minor fixes for PlatformIO (#881)

* Don't escape folders which are already arguments

* Drop "stage" suffix from @platformio dev/platform

.travis.yml

@@ -39,7 +39,7 @@ script:
   - echo -e "travis_fold:start:platformio_test_env_prepare"
   - pip install -U https://github.com/platformio/platformio/archive/develop.zip
   - platformio platform install https://github.com/platformio/platform-espressif32.git#feature/stage
-  - sed -i 's/https:\/\/github\.com\/espressif\/arduino-esp32\.git/*/' ~/.platformio/platforms/espressif32_stage/platform.json
+  - sed -i 's/https:\/\/github\.com\/espressif\/arduino-esp32\.git/*/' ~/.platformio/platforms/espressif32/platform.json
   - ln -s $TRAVIS_BUILD_DIR ~/.platformio/packages/framework-arduinoespressif32
   - echo -e "travis_fold:end:platformio_test_env_prepare"
   - echo -e "travis_fold:start:platformio_test"