v0.0.4

What's changed:

• Improved FPS by 5x - from ~5 to ~25 FPS - same pretrained RNN, but improved accelerometer streamer
• Replaced sensors_plus with flutter_sensors package
• Major refactor - split script into submodules
• Fixed Android Studio development program start bug: #2
• Fixed FPS counter instability: #3

Full Changelog: v0.0.3...v0.0.4