New /Theme based theming system #3

Job	Run time
core-matrix (tg5040)	16s
prepare	13s
build-core (tg5040, c128)	2m 9s
build-core (tg5040, fceumm)	2m 7s
build-core (tg5040, fake-08)	2m 10s
build-core (tg5040, c64)	2m 15s
build-core (tg5040, libretro-cap32)	1m 52s
build-core (tg5040, pokemini)	2m 8s
build-core (tg5040, mgba)	1m 58s
build-core (tg5040, pet)	1m 50s
build-core (tg5040, gpsp)	2m 24s
build-core (tg5040, plus4)	2m 18s
build-core (tg5040, gambatte)	2m 9s
build-core (tg5040, race)	2m 7s
build-core (tg5040, mednafen_vb)	1m 59s
build-core (tg5040, mednafen_supafaust)	2m 24s
build-core (tg5040, pcsx_rearmed)	2m 25s
build-core (tg5040, libretro-uae)	2m 25s
build-core (tg5040, fbneo)	30s
build-core (tg5040, vic)	2m 1s
build-core (tg5040, picodrive)	2m 24s
build-core (tg5040, snes9x)	2m 24s
build-core (tg5040, prboom)	2m 0s
build-core (tg5040, mednafen_pce_fast)	30s
build	0s
	44m 58s

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