Substeps project prompt

Updated editor to check when eclipse fires up, or a new project is created/imported, for the presence of Substeps-y folders in the project. If they are found, it prompts the user to convert the project into a Substeps project.

This is to try and fix issues that were reported, where Substeps features appeared to be missing for users, because the projects they were working on didn't have the Substeps project nature.