Improved mapping hints (for Badgerfish)

I've added the substitutions (mapping hints) from study 1003, and nested plural/singular tags as seen elsewhere in Nexson. Should emit:
```xml
<params>
  <searchContext>All life</searchContext>
  <substitutions>
    <substitution active="true" valid="true">
      <old>Lept</old>
      <new>FOOZ</new>
    </substitution>
    ...
  </substitutions>
</params>
```