added changes after friday meeting

Added changes to SD card, boot select, and GND connect.

Made changes noted in Rev 3 Google Spreadsheet

Luis edits

Schematic was wrong for sd card. Fixed the symbol and footprint for sd card. Motor driver layout needs serious work. Ignore second pcb file. That was just an experiment to see if I could improve the layout.

Need to fix the footprints for the SD card and the L298P Motor Driver.

Final edits minus werid unconnect point on DRC

Fixed Reference Designators

Most of the board is done. Just need to change the layer of the signal lines.

Added power planes. I may go back and change the stack up as well as the layout for the level shifters.