Added `stylus help <prop>`
Added `stylus help <prop>`

tyv/stylus,trixter5/stylus,HossainKhademian/Stylus,Delapouite/stylus,silvaemota/stylus,rstacruz/stylus,Ricardh522/stylus,jameswomack/stylus,johnnycopperstone/stylus,jangarcia/stylus,a-x-/stylus,isaacs/stylus,behzad88/stylus,Zagorakiss/stylus,SimenB/stylus,angryrobot/stylus,cemoulto/stylus,yetone/stylus,baotingfang/stylus,PeterWangPo/stylus,stylus/stylus,Panya/stylus,meteor/stylus,modulexcite/stylus,jonpacker/stylus,ThiagoGarciaAlves/stylus,darwin/stylus,peterkinalex/stylus-1,galenvagen/stylus