* Functions that take Stroke were updated to take Into<Stroke> to make
them consistent with other Into<Stroke> parameters.
* Vec2 implements DivAssign<f32>, to make it consistent with already
implementing MulAssign<f32> and Div<f32>.
* Vec2::angled() uses sin_cos() rather than an individual sin() and
cos() call for an immeasurable but hypothetical performance improvement.
* Disable the lock_reentry_single_thread() mutex test. Lock()ing twice
on the same thread is not guaranteed to panic.
* Closes <https://github.com/emilk/egui/issues/3419>.
* Move scroll bar spacing settings to a `struct ScrollSpacing`
* Add a demo for changing scroll bar appearance
* Add setting for ScrollBarVisibility in demo
* Add `#[inline]` to a `ScrollArea` builder methods
* Refactor how scroll bar show/hide is computed
* Add support for floating scroll bars
* Tweak color and opacity of the scroll handle
* Allow allocating a fixed size even for floating scroll bars
* Add three pre-sets of scroll bars: solid, thin, floating
* Use floating scroll bars as the default
* Fix id-clash with bidir scroll areas
* Improve demo
* Fix doclink
* Remove reset button from demo
* Fix doclinks
* Fix visual artifact with thin rounded rectangles
* Fix doclink
* typos
Emil Ernerfeldt
Phen-Ro