Updates for 2.0.6.

Note that 2 languages were removed and 2 added, per http://www.jrsoftware.org/files/is5-whatsnew.htm.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13339 47890b92-0858-11df-a26f-8b716316a5bc