[Bf-committers] Alembic branches clarification

[Lukas Tönne]

Recently i made a bit of a mistake by doing Alembic development directly in
the gooseberry branch. We have now resolved this by creating a new branch
"alembic" (based on master) which will now be used for all ongoing
development.

It will be merged into "gooseberry" frequently, as the Gooseberry team is
the primary user base at this point.

The original "alembic_pointcache" branch will be discontinued (and probably
be removed to avoid confusion). The difference to the new "alembic" branch
is only in some deprecated early history from 2014, which has since been
mostly reverted and squashed in the newer branch.