MQTT client for Qt
fix to the protocol parser: do not allow mqtt packet lengths exceeding 4 bytes
MOC fixes/improvements
Minor fixes: Qt signal/slot macros for Qt6 compatibility, NULL -> nullptr
1 Resolve the issue #17, using qmqtt under windows with errors. 2 Modified the global.h file, and the export import definitions for libraries. 3 And tested under windows 7 64/32 bit OS with qt-opensource-windows-x86-mingw492-5.5.0-rc or qt-opensource-windows-x86-msvc2013-5.5.0-rc.exe version.