Update version to 2014-09-29b

This update contains security fixes, see the full list of changes here:
https://www.dokuwiki.org/changes#release_2014-09-29b_hrun

It seems github changed the codeload url schema for tar.gz, they removed
the 'legacy' part. I changed the path so now it works.
Merge pull request #9 from vbalazs/bvarga/update_version

Update version to 2014-09-29b