These methods are core behaviors associated with user commands. If you do not implement a method, there is a reasonable default that may do what you need.
Add a file to your project. Override this if you want to put new sources into different fields depending on extension, or other details.
Reverse of project-add-file.
Override this if you want to do something special when the user "compiles" this target.
What to do when a user wants to debug your target.
Easily update the version number of your project.
Edit the file the project’s information is stored in.
Create a new target in a project.
Delete a target from a project.
Make a distribution (tar archive) of the project.
Rescan a project file, changing the data in the existing objects.