Create gray -> grey doc aliases (#5362)

As someone who uses "grey" instead of "gray", it is annoying that my
autocomplete can never find any of the "gray" color related things, so
this adds doc aliases for that.

* [x] I have followed the instructions in the PR template

crates/ecolor/src/color32.rs

@@ -43,8 +43,11 @@ impl Color32 {
 
     pub const TRANSPARENT: Self = Self::from_rgba_premultiplied(0, 0, 0, 0);
     pub const BLACK: Self = Self::from_rgb(0, 0, 0);
+    #[doc(alias = "DARK_GREY")]
     pub const DARK_GRAY: Self = Self::from_rgb(96, 96, 96);
+    #[doc(alias = "GREY")]
     pub const GRAY: Self = Self::from_rgb(160, 160, 160);
+    #[doc(alias = "LIGHT_GREY")]
     pub const LIGHT_GRAY: Self = Self::from_rgb(220, 220, 220);
     pub const WHITE: Self = Self::from_rgb(255, 255, 255);
 
@@ -128,6 +131,7 @@ impl Color32 {
         }
     }
 
+    #[doc(alias = "from_grey")]
     #[inline]
     pub const fn from_gray(l: u8) -> Self {
         Self([l, l, l, 255])

crates/ecolor/src/rgba.rs

@@ -91,6 +91,7 @@ impl Rgba {
         Self([r, g, b, 1.0])
     }
 
+    #[doc(alias = "from_grey")]
     #[inline]
     pub const fn from_gray(l: f32) -> Self {
         Self([l, l, l, 1.0])

crates/egui/src/style.rs

@@ -1015,6 +1015,7 @@ impl Visuals {
     }
 
     /// Returned a "grayed out" version of the given color.
+    #[doc(alias = "grey_out")]
     #[inline(always)]
     pub fn gray_out(&self, color: Color32) -> Color32 {
         crate::ecolor::tint_color_towards(color, self.fade_out_to_color())

crates/epaint/src/image.rs

@@ -124,6 +124,7 @@ impl ColorImage {
     /// Create a [`ColorImage`] from iterator over flat opaque gray data.
     ///
     /// Panics if `size[0] * size[1] != gray_iter.len()`.
+    #[doc(alias = "from_grey_iter")]
     pub fn from_gray_iter(size: [usize; 2], gray_iter: impl Iterator<Item = u8>) -> Self {
         let pixels: Vec<_> = gray_iter.map(Color32::from_gray).collect();
         assert_eq!(size[0] * size[1], pixels.len());