Modified public serving middleware to allow serving from filesystem

[jacobtread]

Description

This change allows files to be publicly served from the data/public folder it was previously intended to be used for #35 however this is postponed (possibly indefinitely) so instead this is being merged separately to allow manual dashboard updating as well as serving custom files (i.e. a custom HTML homepage or other resources you might want the server to share) files in the data/public folder will be served by the server instead of the embedded server files if they are present

Changes

• Public serving middleware can now serve from the file system as well as the embedded files (fs files take priority for serving using the embedded files as fallback)