[suggestion] ESP-IDF component as Platformio library

[Erol444]

As esp-idf compontents docs describe it, platformio scans components folder for any valid component. My suggestion is to extend the platformio scanning to all the libraries of the project if there are any valid ESP-IDF components in there. That way, developers could share ESP-IDF components via the platformio library functionality.

Currently, a manual process of adding the component path of each component(library) to the EXTRA_COMPONENT_DIRS is needed.

[maxgerhardt]

Overlaps https://github.com/platformio/platform-espressif32/issues/453