Add: DSC1001 5x7mm DFN-4 with keepout
As used by the largest variant of the Microchip DSC1001 oscillator:
The keepout isn't dimensioned, so I have used the maximal EP size and added 0.2mm.
As this is an IPC-derived footprint, the dimensions don't 100% match the datasheet:
This MR requires !1127 (merged) to add the rule areas definition handling to the nolead generator.