Disksize Watcher 0.3.0.5

• updated .NET Framework to version 4.8.1
• improved some code
• added diff space

What's Changed

• Add files via upload by @mjohne in #19
• Add files via upload by @mjohne in #20
• Add files via upload by @mjohne in #21
• Add files via upload by @mjohne in #22
• Add files via upload by @mjohne in #23

Full Changelog: 0.2.0.4...0.3.0.5