Force full rebuild when site config changes
Force full rebuild when site config changes

Fixes #1840

fedelibre/hugo,vbatoufflet/hugo,fedelibre/hugo,digitalcraftsman/hugo,abourget/hugo,coderzh/hugo,mdhender/hugo,jygastaud/hugo,tubo028/hugo,tischda/hugo,ffrizzo/hugo,fedelibre/hugo,mayah/hugo,ffrizzo/hugo,soundrussian/hugo,anthonyfok/hugo,jygastaud/hugo,melo/hugo,anthonyfok/hugo,MarkDBlackwell/hugo,Zenithar/hugo,mayah/hugo,MarkDBlackwell/hugo,bogem/hugo,soundrussian/hugo,vbatoufflet/hugo,sprig/hugo,mdhender/hugo,tischda/hugo,anthonyfok/hugo,gohugoio/hugo,mdhender/hugo,abourget/hugo,mitchchn/hugo,tubo028/hugo,bogem/hugo,Zenithar/hugo,melo/hugo,gohugoio/hugo,mdhender/hugo,digitalcraftsman/hugo,gohugoio/hugo,sprig/hugo,fedelibre/hugo,mitchchn/hugo,coderzh/hugo