BOY: fix a nullpointer error
BOY: add "Select Parent" context menu action
BOY: always check if the widget is selectable before selecting it.
BOY: make native text widget's text selectable even it is disalbed.
BOY: change default size and transparent of label and text input widget
BOY: fix a bug that Choice widgets' enable states are incorrect if the
items are from PV.
BOY: add select Parent action
BOY: Add lock feedback and Ctrl+L to grouping container