v2.0.0-alpha.150

Build firmware envelopes on host systems.
Support extracting binary/ubjson from host envelopes.
Add reading-functions to io.Buffer.
Make stringify on lists and sets non-quadratic list.
Allow 'uuid.parse --on-error`' to return null.
Add return type to 'int.stringify radix'.
Use flash registry for buckets on host platforms.
Add snapshot-to-image to toit tool.
Allow io.Data for the storage lib.
Increase host flash registry size to 64MB.
Expose the ESP32 mac address.
Fix out-of-bounds on List.replace.