- composer shape style button (no other composer ones for now- they're
all getting removed with layouts anyway)
- point cluster/displacement renderer buttons
Button widgets for configuring symbol properties were reimplemented
multiple times throughout the codebase. This commit creates a new
standard QgsSymbolButton widget which should be used whenever
a button for configuring symbol properties is required.
Features include:
- automatic use of inline panels whenever possible
- dropdown menu with shortcuts to color settings, copy/pasting colors
- accepts drag and dropped colors to set symbol color
