update INSTALL instructions
update INSTALL instructions

drizt/qjson,gentlefn/qjson,cbranch/qjson-qmakefriendly,gentlefn/qjson,seem-sky/qjson,qlands/qjson,flavio/qjson,coolshou/qjson,drizt/qjson,cbranch/qjson-qmakefriendly,flavio/qjson,qlands/qjson,coolshou/qjson,seem-sky/qjson