work-flow core version + 4 customer branches

[Lukasz Szybalski]

Hello,
Could you tell me how can I create the following?

How can I create this workflow with migrate? Is this possible?

1. core version (main version that affects all customers)
2. + 4 customer branches that have "customized" code for each customer.

I should be able to increment core version by adding common tables, fields.
I should be able to increment the branch for each customer.
I should be able to merge code changes from base to each customer.

How can I setup my environment to get this accomplished?

Thanks,
Lucas