Draft: Added Raspberry Pi library with two footprints for LCD (3.5" & 4")

Footprints for two RPI LCD symbols (merge request issued in symbol lib git repository).

Specs at vendor's wiki page:

• 4" - https://www.waveshare.com/wiki/4inch_RPi_LCD_(A)
• 3.5" - https://www.waveshare.com/wiki/3.5inch_RPi_LCD_(A)

Screenshots

4"

3.5"