update docs to use methods instead of objects for Joi.#{type}
update docs to use methods instead of objects for Joi.#{type}

danielb2/joi,myndzi/joi,lloydbenson/joi,pandeysoni/joi,geminiyellow/joi,cesarmarinhorj/joi,davidbenko9/joi,myndzi/joi,thethanghn/react-native-joi,opyate/joi,jeffbski/joi,ck-lee/joi,robertherber/joi-extended,olistic/joi-extended,bananaoomarang/joi,jagoda/joi,rmoorman/joi,pikselpalette/joi,naitsric/joi,tpiecora/joi