Match score not updated when using query instead of source term

[guuswilmink]

In Usagi, each automatic concept mapping is assigned a match score. This match score is erroneously retained when replacing or removing the automatic mapping. I would propose updating the map score for the replacement concept, rather than retaining the map score for the automatic mapping.

To reproduce this problem:

1. Open a file with source terms to map in Usagi
2. Remove or replace any automatic mapping