Makes line-breaking possibilities more available to grobs

Makes line-breaking possibilities more available to grobs

[MikeSol, 2011-11-06 17:31:55]

Hey all,

This is the first step in a series of patches that I'm gonna try to develop to
create a TextScriptSpanner - a TextScript that automatically word wraps to the
end of a line break and thus doesn't cause oddly deformed lines when markups
fall towards the end of a line.

To do this, the pure height function will need to know the estimated distance
between X columns, which only works if the pure height function can access the
results of the Simple_spacer.  This reorganizes the code so that any grob, in
theory, can access these results.

Cheers,
MS

[pkx166h, 2011-11-06 20:19:47]

Passes make and no reg test diffs

James