v1.0.3

• Fixed force disconnect logic. (#50)
• Added remaining length getting function. (#48)
• Added publish with dup flag function. (#47)
• Added for_each function for stored data. (#44)
• Fixed pubrel re-send algorithm. (#43)
• Added pubrel sending interface. (#41)
• Added sent after callback function. (#39)
• Improved CI environment. (#37)
• Improved documents. (#35, #36)
• Removed generic lambda to meet C++11 (#34)
• Added stored packet clearing function. (#32)
• Fixed QoS2 pubrel sending timing.(#31, #46, #49)
• Fixed remaining length handling logic. (#30)
• Added subscribe and unsubscribe with vector. (#29)
• Added suback with vector. (#28)
• Fixed async subscribe bug. (#26)
• Added connect() with socket. (#25)
• Fixed packet_id accqireing algorithm. (#24, #27)
• Fixed storing QoS1 and 2 packet mechanism. (#23)
• Supported async_write operation. (#21)
• Separated MQTT core from client. Core can be used as server connection. (#20)