[doc] Add docs badge to README
[doc] Add docs badge to README

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rbramwell/forever,nguyen-tien-mulodo/forever,rbramwell/forever,nguyen-tien-mulodo/forever,JJediny/forever,saisai/forever,jotham/forever,jotham/forever,JJediny/forever,Jonekee/forever,kethle/forever,arnabsinha4u/demo-documentation,arnabsinha4u/demo-documentation,ryan321/forever,ryan321/forever,saisai/forever,vcarrera/forever,foreverjs/forever,foreverjs/forever,jqk6/forever,kethle/forever,Jonekee/forever,vcarrera/forever,jqk6/forever