Added a remark to the readme that coverage is GCC only for now
Added a remark to the readme that coverage is GCC only for now

ruppmatt/json,Newbrick/json,aestuarium/json,hunter-packages/json,nlohmann/json,theodelrieu/json,nlohmann/json,hunter-packages/json,theodelrieu/json,Cloudage/json,Newbrick/json,robertmrk/json,whackashoe/json,stanmihai4/json,bestwpw/json,whoshuu/json,kaidokert/json,stanmihai4/json,emvivre/json,kaidokert/json,xzmagic/json,kaidokert/json,xdcesc/json,whackashoe/json,hunter-packages/json,AALEKH/json,daminetreg/json,stanmihai4/json,Newbrick/json,nlohmann/json,nickhen/json,silverweed/json,erichkeane/json