feat(DWG/BK-2020-04-PID-1):Group symbols, adjust titles

- Notes:

  - Adjust group titles in order to reduce text overflow in PNG
    previews of Wikimedia Commons servers (due to said servers lacking
    `osifont` font).

  - Put each symbol into its own SVG group. Put each accompanying text
    in its own SVG group. Put each set of SVG groups into a layer
    according to ISO 10628-2 group.

  - Update each Legend to address registration numbers that fall
    outside the provided patterns.

  - Adjust font sizes in Title and Legend to reduce clipping when
    rendered without `osifont` font.

  - Fix some minor spelling errors.