Add basic Sessions, Web Share Target Level 2 and other features.

[Wojbie]

New Features:

• Audio players added to gallery. (Audio files now automatically show in gallery page)
• If file is not supported by gallery (and shown using filter) as fallback first 256 bytes of file are shown as preview.
• Copy to clipboard buttons on success/error pages.
• Share buttons (in supporting browsers)
• Web Share Target Level 2 - Ability to send files to shitty using phone native share dialog. ( Chrome Canary only amt)
• Notifications support (For now only used by Web Share Target)
• Manifest and Service worker added for use with above features and ready for future expansion ( expanded caching? )

Fixes:

• Brings back Sessions with basic file store and 2 months (untouched) session storage time.
• Copy to clipboard buttons now all work.
• Some handlebars renders were not getting data they needed causing errors in pages.
• Properly wipes corrupted nonces.json and stats.json and reports that to console.

Sidenote: Version bumped in package.json due to change in stats.json format that will require recreating cache after update.

Also includes: 3 variants of poop file and egg.

Images: Phone:

[Wojbie]

That should resolve all the issued. Only thing to note is that express.static will always error ito the log when it hits 416 (Requested Range Not Satisfiable) error. This is nothing to worry about (it don't cause anything and end server still receives correct 416 information but it is something to note that will happen in edge case (looking at empty non media file in gallery).

[Lemmmy]

Ready to merge when you are