docs: Online docs improvements, mostly formatting (AcademySoftwareFoundation#4736)

Signed-off-by: Larry Gritz <lg@larrygritz.com>

Author: lgritz

src/include/OpenImageIO/image_span.h

@@ -98,7 +98,7 @@ template<typename T, size_t Rank = 4> class image_span {
     // clang-format off
     /* clang_format gets confused by this */
 
-    /// Copy constructor from image_span<T> to image_span<const T>.
+    /// Copy constructor from `image_span<T>` to `image_span<const T>`.
     template<typename U, size_t R,
              OIIO_ENABLE_IF((std::is_same_v<std::remove_const_t<T>, U>)
                             && std::is_const_v<T> && !std::is_const_v<U>
@@ -112,7 +112,7 @@ template<typename T, size_t Rank = 4> class image_span {
     }
     // clang-format on
 
-    /// Construct from span<T> and dimensions, assume contiguous strides.
+    /// Construct from `span<T>` and dimensions, assume contiguous strides.
     image_span(span<T> data, uint32_t nchannels, uint32_t width,
                uint32_t height, uint32_t depth = 1)
         : image_span(data.data(), nchannels, width, height, depth)
@@ -126,7 +126,7 @@ template<typename T, size_t Rank = 4> class image_span {
     /// same strided data as the operand.
     image_span& operator=(const image_span& copy) = default;
 
-    /// image_span(x,y,z) returns a strided_ptr<T,1> for the pixel (x,y,z).
+    /// image_span(x,y,z) returns a `strided_ptr<T,1>` for the pixel (x,y,z).
     /// The z can be omitted for 2D images.  Note that the resulting
     /// strided_ptr can then have individual channels accessed with
     /// operator[]. This particular strided pointer has stride multiplier 1,
@@ -212,8 +212,8 @@ template<typename T, size_t Rank = 4> class image_span {
                                            ystride(), zstride(), m_chansize);
     }
 
-    /// Convert an image_span<T> to an image_span<std::byte> representing the
-    /// same sized and strided memory pattern represented un-typed memory.
+    /// Convert an `image_span<T>` to an image_span<std::byte> representing
+    /// the same sized and strided memory pattern represented un-typed memory.
     /// Note that this will not work (be a compiler error) if T a const type.
     image_span<std::byte> as_writable_bytes_image_span() const noexcept
     {