- Features:
  - `HSLColor` now implemented as a dataclass using slots for efficiency and performance.
  - Color scales concatenation. Now it is possible to concatenate several color scales into a
    single one.
  - Color scales lerp'ing. Now colors can be created given a color scale and a position in it.
  - Color scales conversion:
    - To SVG linear gradients as `xml.etree.ElementTree.Element` trees.
    - To Plotly color scales.
  - Extraction of color sequences from color scales.