Fix display and translation of vocabulary values.
Compare the result of at_utils.translate call in these tests.

It is nice to know that the call does not raise an exception, but we
want a correct answer too.
Fix translating integer display lists.

Refs pull request #25.
Test that translating unicode values from vocabs goes right.

No longer use the unicodeEncode python skin script here, as the part we need is really simple.
Merge pull request #26 from plone/maurits-vocab-fixes

Various vocabulary fixes, mostly for translations and IntDisplayLists