Update index.md
Update index.md

Updated documentation, mkdocs help is no longer valid, suggested mkdocs --version instead.
vi4m/mkdocs,kubikusrubikus/mkdocs,tedmiston/mkdocs,pjbull/mkdocs,tedmiston/mkdocs,jamesbeebop/mkdocs,mlzummo/mkdocs,pjbull/mkdocs,tedmiston/mkdocs,justinkinney/mkdocs,samuelcolvin/mkdocs,williamjmorenor/mkdocs,gregelin/mkdocs,simonfork/mkdocs,samuelcolvin/mkdocs,samuelcolvin/mkdocs,jimporter/mkdocs,jimporter/mkdocs,justinkinney/mkdocs,rickpeters/mkdocs,hhg2288/mkdocs,jeoygin/mkdocs,mkdocs/mkdocs,lukfor/mkdocs,lukfor/mkdocs,dmehra/mkdocs,michaelmcandrew/mkdocs,longjl/mkdocs,mlzummo/mkdocs,nicoddemus/mkdocs,hhg2288/mkdocs,davidgillies/mkdocs,waylan/mkdocs,peter1000/mkdocs,fujita-shintaro/mkdocs,pjbull/mkdocs,lbenet/mkdocs,simonfork/mkdocs,gregelin/mkdocs,lbenet/mkdocs,fujita-shintaro/mkdocs,peter1000/mkdocs,longjl/mkdocs,longjl/mkdocs,cnbin/mkdocs,mkdocs/mkdocs,dmehra/mkdocs,cnbin/mkdocs,michaelmcandrew/mkdocs,lukfor/mkdocs,d0ugal/mkdocs,mlzummo/mkdocs,kubikusrubikus/mkdocs,jimporter/mkdocs,simonfork/mkdocs,dmehra/mkdocs,nicoddemus/mkdocs,davidgillies/mkdocs,rickpeters/mkdocs,davidgillies/mkdocs,ramramps/mkdocs,michaelmcandrew/mkdocs,williamjmorenor/mkdocs,jeoygin/mkdocs,nicoddemus/mkdocs,d0ugal/mkdocs,williamjmorenor/mkdocs,ramramps/mkdocs,vi4m/mkdocs,rickpeters/mkdocs,justinkinney/mkdocs,jeoygin/mkdocs,hhg2288/mkdocs,jamesbeebop/mkdocs,waylan/mkdocs,cnbin/mkdocs,peter1000/mkdocs,jamesbeebop/mkdocs,kubikusrubikus/mkdocs,lbenet/mkdocs,d0ugal/mkdocs,vi4m/mkdocs,waylan/mkdocs,ramramps/mkdocs,fujita-shintaro/mkdocs,gregelin/mkdocs,mkdocs/mkdocs