Enable automatic linebreaking

Lines are filled based on an algorithm that balances filling the line with keeping mathematical sub-expressions such as "ax + b" together on a line.

Enable dsi-linebreakop linebreak style

MathML operators that have dsi:linebreakop="true" have special breaking behavior. Typically, relational symbols (such as "=") are marked with dsi:linebreakop="true". For the purposes of description, assume that all occurrences of "=" are marked as being dsi:linebreakop="true".