Create wheel-speed-tester-rev2.sch

Create PCB Tester rev1.docx

Digipot implementation

Reformatting some files

Changed 555 timer capcitors to 1uF. See excel sheet

Added excel info file

Switched Resistor associated with astable 555 timer to 43k from 100k

Changed resistor array values to usable values found in shop b/w 1k and 20k

Replaced 715 ohm resistors for current source with 1ks for +- 4mA tolerance

Revert "Replaced jumpered resistors with digipot" This reverts commit 3ec4fa1ead4dac01abca876bc4bd114703f8871f.