Auto merge of #110 - servo:create_factory, r=metajeck
Auto merge of #110 - servo:create_factory, r=metajeck

Use functions in master.cfg to share code between factory definitions.



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UK992/saltfs,servo/saltfs,setupminimal/saltfs,ALikhachev/saltfs,UK992/saltfs,rwaweber/saltfs,rwaweber/saltfs,ALikhachev/saltfs,rwaweber/saltfs,ALikhachev/saltfs,setupminimal/saltfs,setupminimal/saltfs,UK992/saltfs,servo/saltfs