Changeset 38833

Importing Twenty Seventeen, our new default theme for 2017, set for 4.7.

With a focus on business sites, it will let you get down to business in style. Initial development occurred on GitHub. See: ​https://github.com/WordPress/twentyseventeen

Props melchoyce, laurelfulford, davidakennedy, grapplerulrich, manishsongirkar36, joefusco, smyoon315, b-07, rabmalin, mrahmadawais, hardeepasrani, implenton, acmethemes, claudiosanches, valeriutihai, pressionate, sgr33n, doughamlin, zodiac1978, tsl143, nikschavan, joshcummingsdesign, enodekciw, jordesign, patilvikasj, ryelle, mahesh901122, williampatton, juanfra, imnok, littlebigthing, mor10, samikeijonen, celloexpressions, akshayvinchurkar, davidmosterd, hiddenpearls, netweb, pratikchaskar, taggon, nukaga, ranh, yoavf, karmatosed, sandesh055, adammacias, noplanman, yogasukma, binarymoon, swapnilld, swissspidy, joyously, allancole, rianrietveld, sixhours, alex27, themeshaper, mapk, leobaiano.

See #38372.