[scribus] Align text forced justified and non breaking space

[Andreas Vox]

> From: Gregory Pittman <gpittman at iglou.com>
> 
> On 04/11/2014 08:17 AM, Peter Nermander wrote:
>>> I'm sure you are right about the "original" meaning of non-breaking
>>> spaces. Let
>>> me say it other words: It would be nice to have two different kinds of
>>> spaces:
>>> one with fixed width and a streching one. It doesn't matter if you call it
>>> 
>> 
>> There are plenty to choose from:
>> 
>> https://www.cs.tut.fi/~jkorpela/chars/spaces.html
>> 
> I think the important question is about what happens to a non-breaking
> space with full justification. Is it subject to being widened? If so, I
> think Scribus should exempt these from any stretching.
> 

I think we need a nonbreaking space that stretches when justified.

If you really want a fixed width space, use one of enspace, emspace (1,1/3,1/4,1/6)
or figurespace. In the future Scribus will emulate those (and other spaces)
if they are not present in the font. 
Currently my idea is to make only spaces which are defined as a multiple of a quad or 
have "non-breaking" in their name non breaking and all others breaking. For a sequence
of spaces the last one would determine if there is a break or not.

Another idea is to implement french spacing in the layouter. In that case the layouter would
convert any space, nbspace, thinspace, narrow no-break space or missing space to the
defined French thin space in positions where required. To avoid this space in special cases
you'd have to use zero width no-break space or one of the fixed  spaces. 
In any case there would be no break position.

/Andreas