Move cover page colour and blank coloured end page to doc-specific files. That way output where the colour isn't appropriate, such as Nook or the newly introduced A4Lulu output (which is the A4 book but with white cover page and no end coloured page, and so suitable for using as the content on Lulu, where the cover is separate) can omit the colour.

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−X:1
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−T:Staffordshire Hornpipe, The
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−M:C
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−L:1/8
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−S:Flamborough
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−K:Gmaj
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−(3DEF |\
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−G2e2 c2AG | FAd2 B2A2 | G2e2 c2AG | FAd2 DFAF | G2e2 c2AG |
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−FAd2 B2G2 | cedc BGAF | G2B2 G2 :|\
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−|: z2 | B2A2 G2F2 | EF (3GFE D2 EF | GFGA BABc |
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− d2c2 A2d2 | B2A2 G2F2 | EF (3GFE D2d2 | e2dc BGAF | G2B2 G2 :|