SLB Alpha Firmware B5.0.2

• Updated Ethernet driver to improve stability and performance
• Updated Trinamic driver to allow board to boot with stepper power disabled (E-stop)
• Updated Trinamic driver to restore motor function after booting with stepper power disabled
• Updated probe plugin to address SLB-58
• Flipped pin assignment for MAC1/2 in firmware
• Made lots of small tweaks to EEPROM titles and descriptions to improve clarity