lan_vdd1A centre via

Tented vias under stlink

added 3V3 decoupling for RMII ferrite

Added more GND connections and cleaned some component placements.

Added GND connections to missing components.

Added gnd shield under PHY oscillator

Expanded polygon cutouts around breakout through-holes, cleaned up some silk-screen positioning.

Final ethernet touchups

Rerouted ethernet interface

Updated rmii keepout regions again...