Add reed relais from Standex/Meder (SIL/DIP/MS)

Created by: jkriege2

• added reed relais from Standex Meder (SIL, MS and DIP-series)
• 3D sources: https://github.com/KiCad/kicad-packages3D-source/pull/77
• 3D exports: https://github.com/KiCad/kicad-packages3D/pull/215
• footprints: https://github.com/KiCad/kicad-symbols/pull/156
• datasheets:
  • https://standexelectronics.com/wp-content/uploads/datasheet_reed_relay_DIP.pdf
  • https://standexelectronics.com/wp-content/uploads/datasheet_reed_relay_SIL.pdf
  • https://standexelectronics.com/de/produkte/ms-reed-relais/
  • https://standexelectronics.com/de/produkte/ums-reed-relais/

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