User folder centralisation

[MiPnamic]

While re-reading and thinking about #19 and #3, I was wondering if the basic config file should be placed inside a .gitnapped folder in the User folder, instead of a single preference file (which we can call preferences instead of .gitnapped as stated in #19)

Recap:

• Identify User folder (system's specific)
• create a .gitnapped folder if it doesn't exist
• Change the yaml file structure into something else #3 can still happen inside the .gitnapped folder by default
• User settings on local .gitnapped file #19 can still happen using a different filename?! maybe a ~/.gitnapped/preferences