Driver packages should be isolated

[mariobalanica]

• Copy driver files to the driver store rather than Windows\System32\drivers
• Use device interfaces instead of hardcoded driver paths for:
  • bcm2836pwm
  • rpiq
  • vchiq

[Marcinoo97]

make it adaptable for WCOS too

[driver1998]

Now I added package manifests for IoT Core ARM64 (#43), hopefully they'll also be useful for WCOS.