V8.0.8 released

Several fixes and changes with window layouts (workspaces): - The wording "window layouts" has been used for historical reasons but workspace is more common. - Turning workspace buttons into drop down button. - Rearranged menu items in menu View/Workspaces. - Removed "Arrange Windows" function. It's not really needed anymore since the windows snap to each other now. It was often causing confusion when it has undesired results. - Removed embedded windows mode. - Reduced flickering when switching workspaces. - When holding Ctrl on window move/sizing, snapping is disabled. - When sizing main window then windows inside the main window keep their aspect ratio. Middle mouse button on brush container slot deletes the slot. Fix: Now stopping animation playback when dropping a file onto the UI. Fix: Formula paint mode was applied multiple times during stroke. Fix: Using "Save As" with brush container and cancel showed an error. Fix: Color editing dialog not working correctly. When using the dialog for editing a single color in non-palette mode, e.g. in the preferences for the transparency checker pattern colors, then the RGB edit fields did not work correctly. Also, a display glitch at the color range gradients of a single channel sometimes showed pure white instead of the gradient when opening the dialog. Fix: Intro dialog interfered with canvas window and did not close. Fix: A layer blend mode different than "Normal" could not be reset to "Normal". Fix: It could happen that some of the application windows use a wrong width.