evolve: write data to evolvestate in case on conflicts in phase-divergence
This patch makes phase-divergence resolution write data to evolvestate instead
of graftstate. The `evolve --continue` handling of phase-divergence is broken
which will be done in upcoming patches.
evolve: explicitly turn revs to list before storing into evolvestate
The cbor library which we are using cannot handle encoding and decoding Python
sets, and revs was set there. Let's convert revs explicitly to list to make sure
we don't try writing sets.