preferences file with id/path remapping

[allaryin]

Create a prefs file for fastpack to use that allows one to save a list of mod id/path rename and config file ownership preferences. Provide a standard download.

Examples:

• ensure that Pam's Harvestcraft has an id of 'harvestcraft' but a path of 'pams-harvestcraft'
• ensure that Decocraft has an id of 'decocraft' and not 'props'
• ensure that Advanced Generators doesn't have an id of 'generators'
• ensure that a strangely named config file is associated with the correct mod (would resolve Simple Void World configs being matched to Simply Jetpacks #4)