Able to rename a module during a migration

[sebalix]

Is your feature request related to a problem?
Able to rename a module during a migration. E.g. OCA/knowledge#367

Describe the solution you'd like
Add an option --rename-to:

$ oca-port 15.0 16.0 knowledge --rename-to document_knowledge

We could also rename the module in the past git history, so under the hood it could perform a
git filter-branch --tree-filter 'if [ -d old_module_name ]; then mv knowledge document_knowledge; fi' HEAD