A supplied abbreviation can have tokens prepended

In https://github.com/lascivaroma/cil004-00000/blob/master/data/cil004-00000/00003/cil004-00000.00003.manfred-lat1.xml,

```xml
ae<supplied reason="lost"><expan><abbr>d</abbr><ex>ilem</ex></expan></supplied>
```

should be

```xml
<expan><abbr>ae<supplied reason="lost">d</supplied></abbr><ex>ilem</ex></expan>
```