Latex backend: Elliminated some parasytic spaces in kprefix/ksuffix/kmiddle.
Latex backend: Refactoring: prefix, content, suffix are nos separate arguments for mcell.
Latex backend: improved line breaking inside cells.
-- Improve rendering of prefix/suffix ellipses. They should not be affected by line breaking algorithms.
-- Support for long rewrites with additional content inside cells.
Latex backend: improved line breaking inside cells. Most complex case: nested cells with rewrite.
Latex backend: Finished implementing line breaking. Eliminated the last overflowing rule, eliminated some more parasytic spaces, allowed maximum space for cells in width for most efficiont rendering.