Search catalog uses incorrect plural form when there's only one dataset

[amoeba]

Steps to reproduce:

1. Set up a fresh Metacat install w/ MetacatUI
2. Insert one metadata record (e.g., EML 2.1.1)
3. Browse to /data
4. See

Datasets 1 to 1 of 1

Expected behavior: Dataset 1 to 1 of 1