attDef/desc context disregarded

[peterstadler]

relocating from TEIC/TEI#835.

---

I've noticed that in the following example, Roma reads manuscript folios as the description for the attribute as a whole, rather than using the default TEI :

<classSpec ident="att.dimensions" mode="change" module="tei" type="atts">
<attList>
<attDef ident="unit" mode="change">
<valList mode="replace" type="closed">
<valItem ident="folios">
<desc>manuscript folios</desc>
</valItem>
<valItem ident="lines">
<desc>lines of text</desc>
</valItem>
<valItem ident="words">
<desc>words of text</desc>
</valItem>
<valItem ident="chars">
<desc>characters of text</desc>
</valItem>
<valItem ident="mm">
<desc>millimetres</desc>
</valItem>
</valList>
</attDef>
</attList>
<classSpec>