Update NASPA-related licensing

[jfultz]

Updated licensing text should be:

NASPA Word List 2018 Edition © NASPA 2018. The copy
included in this app is licensed for personal use. You may not use it for any
commercial purposes.

NASPA would also like a hyperlink to www.scrabbleplayers.org added to the above text.

Also, the logo is janky(*...Seriously, not even CSW?!) on high-res screens. I should get or generate a better one from the PDFs here:
https://www.scrabbleplayers.org/w/Style_guide#Logos

Specifically, if Qt's SVG renderer works well, then I could probably convert this version from PDF to SVG using InkScape. Failing that, I can at least generate some high-res bitmaps.