Adjust Pipeline/Step namespaces

[Toastbrot236]

This PR is the first of multiple PRs intending to refactor and change various things on Refresher, in the hopes of improving maintainability and making it easier to add additional features.

This PR does the following:

• Pipelines and Steps were moved into multiple separate namespaces and directories, since we have many of them now. This way they're not as messy anymore in my opinion.
• LogType is no longer a global import, so all log calls now have to specify their category enum value as e.g. LogType.PS3 instead of just PS3
• The Pipeline.Id property was removed since it's not used, and will likely not be used anytime soon
• Steps now have a Name property which contains a short, user-friendly description on what the step does. In the future, the GUI should show the name of the current step being executed using this property.