DDK v2.0 related checkin

+ Renamed usb_driver_kit to ddk
+ Corrected the description swap between .cmp & .stf files in the README.md
+ Final schematic (w/ old annotations preserved)
+ Final footprint associations (w/ old annotations preserved)
+ Board layout & related stuff are still the old ones
DDK v2.0 related checkin #2

+ Final board layout done (for the schematic & footprint associations, already checked-in)
	> Alongwith, placed eSrijan & OSHW's logos as modules in board's copper & silkscreen layers
	> So, adding the corresponding module related files, as well
+ Consequently, plotted the same in .ps format & then converted to .pdf format (using ps2pdf)
	> Front, Back, Mask_Front, Mask_Back, SilkS_Front, SilkS_Back
	> Alongwith generated the drill file as well
+ As the plot file names have changed, deleted the earlier boards' (DDK v1.*) .ps & .pdf files