The ALM rangers never sleep. Now they have created a Release Manager Workflow Migrator:
Looking to export a Release Management agent based deployment pipeline so that it can be reused in the Release Management service in Visual Studio Team Services (VSTS)?
We have released a migration tool and associated guidance as an open source project, allowing you to use “as is” or contribute to the project. If a Pull Request shows up at the door for the source or documentation, it will definitely be considered.
So if you are using Release Manager today and want to switch to the new Release Management service in VSTS, this will be a great help!
More information: https://github.com/ALM-Rangers/Migrate-assets-from-RM-server-to-VSTS