Add borderline
Fix tab title border issue and docking position issue
Update tabs-border lines and docking issue
Fix merge conflict
Fix merge error
Merge remote-tracking branch 'origin/feature/osgviewerQt' into slohia

Conflicts:
	include/mainwindow.h
	src/mainwindow.cpp
Merge remote-tracking branch 'origin/feature/osgviewerQt' into slohia

Conflicts:
	include/mainwindow.h
	qtWidgets/src/tree_view.cpp
	src/mainwindow.cpp
Merge remote-tracking branch 'origin/feature/tabs' into slohia

Conflicts:
	include/mainwindow.h
	qtWidgets/ui/inspector.ui
	qtWidgets/ui/visualizer.ui
	src/mainwindow.cpp
Temporary commit while testing slider and spinbox
Fix merge conflict
Fix merge conflict
 Fix merge error in inspector.ui
connect slider and spinbox, defer doublespinbox
Update inspector.ui to set ranges in designer
Trying to generate custom widget and promote it in inspector.ui, not there yet
Fix merge conflict in mainwindow.h
Connect the slider with joint motion in grip, feasibility shown.
Testing custom widget and promotion, almost there
Fix bug in unit conversion
Update custom widget slider to send and get double value numbers -180.0~180.0