esp32-idf framework def for platformio

manifest.json

{
  "framework-espidf": [
    {
      "url": "https://github.com/rohansingh/esp-idf/archive/v3.0.0-rc1-pio-1.zip",
      "version": "3.0.0-rc1",
      "system": "*",
      "sha1": "5da85a8f765e50eac0e270d3676b299adbc065a2"
    }
  ]
}