added new comment
added for different Month length and leap year

"(Done)" comments have been added before the to-do list which have been
dealt.  Please check them.
Custom Plot function is generated.  It needs check with database

Some to-do lists have been done in Mainwindow.cpp
Plot function checked and improved

Thanks for Andrew fixing the database access problem.  The plot function
has been checked and improved.  It looks working properly.
Add connection timer
Push all files for syncing
Merge remote-tracking branch 'origin/joye' into joye

Conflicts:
	WaterMeterGUI/WaterMeterGUI.pro.user
	WaterMeterGUI/databasemanager.cpp
	WaterMeterGUI/databasemanager.h
	WaterMeterGUI/mainwindow.cpp

	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/debug/moc_mainwindow.cpp

	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/debug/moc_qcustomplot.cpp

	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/debug/moc_serialmanager.cpp

	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/debug/moc_settingsdialog.cpp
	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/ui_mainwindow.h

	build-WaterMeterGUI-Desktop_Qt_5_3_MSVC2013_64bit-Debug/ui_settingsdialog.h