replace add with set because it needs to be possible to override the default headers
replace add with set because it needs to be possible to override the default headers

when using "add", the headers are merely concatenated anyway. This can easily be achieved still & therefore this change does not remove any ability

redlinesolutions/JSONModel,icanzilb/JSONModel,jianwoo/JSONModel,jsonmodel/jsonmodel,yarec/JSONModel,MellongLau/JSONModel,liwangbest/JSONModel,xxclouddd/JSONModel,zwcshy/JSONModel,youprofit/JSONModel,hfossli/JSONModel,chenkaige/JSONModel,cczallen/JSONModel,SanjoDeundiak/JSONModel,jianwoo/JSONModel,scottdinggo/JSONModel,SummerHF/JSONModel,liuyujing/JSONModel,dbachrach/JSONModel,SatanWoo/JSONModel,billinghamj/JSONModel,CareEvolution/JSONModel,kerrmarin/jsonmodel,dalu93/JSONModel,zhou18520786640/JSONModel,LiuShulong/JSONModel,iwakevin/JSONModel,db42/JSONModel,AlJaMa/JSONModel,billinghamj/JSONModel,MaWenxing/JSONModel,zwcshy/JSONModel,SongYuJie1989/JSONModel,ThirakornP/JSONModel,NiuMengFei/JSONModel,xunan623/JSONModel,SampleLiao/JSONModel,ernestopino/JSONModel,huiping192/JSONModel,izrie/JSONModel,yunzhongyoulong/JSONModel,ramoslin02/JSONModel,johnmyqin/JSONModel,TerryAsh/JSONModel