Spectrum v1.2.0

Spectrum v1.2.0 released! 🥳

What's new:

• Graphview implemented
• Landscape support
• Database added
• Audio playback is functional
• Graph update speed can be changed
• Keep screen on

What happened to v1.1.0 and earlier?
I didn't upload those releases because they were still WIP. As of v1.2.0, it is stable and ready to use.