TP-Link TL-SG116[P] Switch 19" Rackmount Refined

A 19" rackmount bracket for the TP-Link TL-SG116 (and TL-SG116P PoE) Switch

A few tweaks to the original to refine the model.

Notably:

• Section lengths adjusted to be more evenly sized
  • Now easily fits on an Ender 3 V2 bed
  • Provides more rigidity from the Switch itself being further inside the R/L brackets
• Slots on L/R brackets for ventilation (maybe more important for PoE variant)
• Reduced switch opening height 1mm for closer fit
• Rounded corners and lengthened cage nut screw holes for horizontal adjustment
• Thinner front to match other rackmount ear protrusions