[skip ci] Fixed link to contributing.md from readme
[skip ci] Fixed link to contributing.md from readme

alouanemed/coderwall,ronaldotijucas/coderwall,agileknight/coderwall,alouanemed/coderwall,ggaabe/coderwall,sekouzed/coderwall,sekouzed/coderwall,agileknight/coderwall,alouanemed/coderwall,wiserfirst/coderwall,ggaabe/coderwall,pushkar-mishra/coderwall,ggaabe/coderwall,pombredanne/coderwall,pushkar-mishra/coderwall,assemblymade/coderwall,wiserfirst/coderwall,assemblymade/coderwall,wiserfirst/coderwall,coderwall/coderwall,assemblymade/coderwall,santoshdeshpande/coderwall,sekouzed/coderwall,frootloops/coderwall,wiserfirst/coderwall,AVGP/coderwall,coderwall/coderwall,santoshdeshpande/coderwall,ronaldotijucas/coderwall,pombredanne/coderwall,coderwall/coderwall,DylanKojiCheslin/coderwall,frootloops/coderwall,agileknight/coderwall,pombredanne/coderwall,DylanKojiCheslin/coderwall,ronaldotijucas/coderwall,AVGP/coderwall,assemblymade/coderwall,seuros/coderwall,trinitronx/coderwall,ronaldotijucas/coderwall,trinitronx/coderwall,alouanemed/coderwall,trinitronx/coderwall,seuros/coderwall,agileknight/coderwall,seuros/coderwall,seuros/coderwall,pushkar-mishra/coderwall,pombredanne/coderwall,pushkar-mishra/coderwall,DylanKojiCheslin/coderwall,AVGP/coderwall,trinitronx/coderwall,frootloops/coderwall,sekouzed/coderwall,santoshdeshpande/coderwall,coderwall/coderwall