Fixed a typo.

git-svn-id: https://svn.cms.waikato.ac.nz/svn/weka@10924 e0a1b77d-ad91-4216-81b1-defd5f83fa92
Fixed a typo.

git-svn-id: https://svn.cms.waikato.ac.nz/svn/weka@10925 e0a1b77d-ad91-4216-81b1-defd5f83fa92