Bug#815252: colord: please make the build reproducible (timestamps)

[Christopher James Halse Rogers]

Thanks for the patches! I'll add the necessary autofoo checks and 
propose them upstream.

Would it make more sense for cd-it8 to also respect SOURCE_DATE_EPOCH? 
Is there a reason other than ‘it was simpler to just disable 
timestamps’ (before I try duplicating the cd-create-profile logic 
into that patch).