schema: resolve att def duplications

[kepper]

There are more than 100 attributes sharing their names with other attDefs. Most of them are perfectly sensible, because they are used in different contexts, and have quite different models – they just share their names, which are perfectly appropriate in their context. Sometimes, however, <attDef>s have just been copied over to not interfere with the class system. These cases are maintenance issues, which this PR tries to resolve. None of these changes should affect MEI instances.

[rettinghaus]

This is super, thanks. Please give me the time to have a proper look at this.

[musicEnfanthen]

Thanks @kepper for this consolidation work.

[kepper]

Just for reference: I had another look at mensural stems, and I believe it's best to leave the situation as it is for now. We can revise as soon as we have the discussion around #1159 (which I'll push to someday…)

[rettinghaus]

Looks great, thanks for the work! Some ideas for improvements.

[rettinghaus]

Also I'm a bit hesitant to extract att.coordinated.ul. Why is att.coordinated inappropriate there?

[musicEnfanthen]

@kepper Would you have time to address conflicts and comments?

[bwbohl]

ping @kepper

[kepper]

Also I'm a bit hesitant to extract att.coordinated.ul. Why is att.coordinated inappropriate there?

<graphic> has it's own @ulx and @uly definitions, which seems inappropriate. As I didn't want to change the footprint of the the schema, using att.coordinated on <graphic> would be incorrect, so separating out the upper left coordinates in a class of their own seems to be the better way. Of course it is also possible to discuss whether <graphic> should use other attributes, but that seems like a bigger change than what we have so far. Also, it seems like combining the new att.coordinated.ul with @width and @height might allow other approaches to describe rectangles in the future (not saying this is good or bad – just saying it becomes possible…).

[bwbohl]

@kepper could you please resolve conflicts and address the comments above?