ESP32 mesh nodes have identical mesh id

[eporocrail]

The ESP8266 and the ESP32 have a "unique" MAC address. It consists of six byte in HEX format.
With the ESP8266 the mesh id is created taking the RIGHT six characters of the twelve of the MAC address.
With the ESP32 the mesh id is created from the LEFT most eight characters of the twelve of the MAC address.

Assuming that the left byte is the most significant byte of the MAC address the possibility that in a mesh nodes have the same mesh id is with the ESP32 much higher than with the ESP8266.

And I do have ESP32 nodes with the same id.
Please apply the same algorithm to create the mesh id for the ESP32 as for the ESP8266 module.

[alexmogavero]

I have added a walk around to this issue in my pull request #84 it is a method to set the id manually