Mapping between Elyra version and pipeline metadata version

[ptitzler]

When a user creates a pipeline using the Visual Pipeline Editor, the generated pipeline file contains an internal metadata version identifier. When a user opens a pipeline in the editor the file's version identifier is compared with the metadata version that the editor supports. If there's a mismatch

• the pipeline metadata must be migrated if the pipeline's metadata version < editor metadata version (a dialog is displayed when the pipeline is opened in the editor)
• an error is raised if editor metadata version < pipeline's metadata version and Elyra needs to be upgraded to support the pipeline.

[ptitzler]

The following table defines which pipeline metadata file version Elyra supports.

Pipeline version history:

Pipeline version	Elyra version	pipeline-editor version
1	v1.0.0	n/a
2	v1.1.0	n/a
3	v1.2.0	n/a
4	v3.0.0	v0.11.0
5	v3.1.1	v1.2.0
6	v3.3.0	v1.4.0
7	v3.4.0	v1.5.0

If an unsupported version error is raised trying to open a pipeline file, upgrade to a newer version of Elyra that supports the pipeline's version.