build-support/factor.sh: allow user to specify NO_UI
build-support/factor.sh: allow user to specify NO_UI

sarvex/factor-lang,dch/factor,tgunr/factor,bpollack/factor,tgunr/factor,nicolas-p/factor,sarvex/factor-lang,AlexIljin/factor,slavapestov/factor,factor/factor,nicolas-p/factor,bpollack/factor,bpollack/factor,AlexIljin/factor,bjourne/factor,dch/factor,bjourne/factor,nicolas-p/factor,slavapestov/factor,bpollack/factor,factor/factor,tgunr/factor,bpollack/factor,bjourne/factor,factor/factor,bjourne/factor,factor/factor,nicolas-p/factor,nicolas-p/factor,sarvex/factor-lang,mrjbq7/factor,factor/factor,bjourne/factor,tgunr/factor,mrjbq7/factor,mrjbq7/factor,dch/factor,AlexIljin/factor,dch/factor,bpollack/factor,sarvex/factor-lang,bpollack/factor,mrjbq7/factor,slavapestov/factor,slavapestov/factor,sarvex/factor-lang,slavapestov/factor,mrjbq7/factor,bjourne/factor,sarvex/factor-lang,dch/factor,AlexIljin/factor,AlexIljin/factor,bjourne/factor,AlexIljin/factor,sarvex/factor-lang,slavapestov/factor,AlexIljin/factor,slavapestov/factor,tgunr/factor,dch/factor,factor/factor,nicolas-p/factor,mrjbq7/factor,tgunr/factor,nicolas-p/factor