Added schematic. Improved footprint.

Footprint includes outer dimensions for the three sizes of readers.
Corrected layout to work with breadboard.
Reversed layout to make labels visible when attached.
Added version v20 to bottom copper.
Updating silkscreen to both sides, adding in OSHW logo, adding in bottom copper for version number
Fixing isolate and upping trace widths
Updating README with new part information