Validate folder name uniqueness on folder renames on folder moves/copying.
Fix for #304: make 'copy files and/or folders' work when the current folder is the root folder.
Make sure the error message on duplicate folders works with unicode characters as well.
Merge pull request #305 from kux/issue_295

Fix issues #295 and #304
adds kux to AUTHORS
updates travis packages sources for Django 1.5
updates tox test settings
fixes typo in docs
version bump to 0.9.4a1
Merge branch 'develop' of github.com:stefanfoulis/django-filer into develop
Remove unused method Clipboard.empty

This method seems to be a left-over from django-image-filer when the clipboard was named a bucket
Even if the method would be used, it would raise an AttributeError since it has no bucket_items attribute
Merge pull request #306 from kux/develop

Remove unused method Clipboard.empty
adds translations from transifex
version bump to 0.9.4
Merge branch 'release/0.9.4' into develop
version bump to 0.9.5a1.dev1
adds next entry in history
limit django-polymorphic version to 0.4.0, since 0.4.2 seems to break with django-mptt
updates testsuite to use django-1.3 compatible version of django_polymorphic. don't enforce old version for everybody.
Fix error raising in FILER_DEBUG mode

Re-raising the error modifies the traceback and makes it hard to debug.
Just calling raise in a except statement re-raises the error with
its full traceback, making it easier to debug.