add texas SOP-8 package

Created by: balcer

http://www.ti.com/lit/ds/symlink/iso1050.pdf

https://github.com/KiCad/kicad-symbols/pull/1342

I found 3D model on Texas Instrument website: https://webench.ti.com/cad/dlbxl.cgi/newstep/DUB0008A.stp

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