Add Toshiba SOP-18_7.495x11.515mm_P1.27mm

This is a SOP (chunky SOIC!) from Toshiba that's required by the TBD62785AFWG symbol - part of kicad-symbols!4139 (merged)

And also for one of the variants of the TBD62783A part that we already have (but it's not an atomic symbol yet)

Datasheet: https://toshiba.semicon-storage.com/info/TBD62783AFG_datasheet_en_20160511.pdf?did=30523&prodName=TBD62783AFG

And a fitup with the 3D model from Digikey (can't find one at Toshiba):

It does feel a bit odd to have a 3 decimal place number, but this is also done, eg for SOIC-8_5.275x5.275mm_P1.27mm and quite a few others.

Footprint MR: kicad-footprints!3375 (merged)

Symbol MR that uses this: kicad-symbols!4139 (merged)