Delete 'waveimport' folder. (Replaced by 'expimp')

https://reviews.apache.org/r/12681/

Should have been deleted as part of https://reviews.apache.org/r/7958
but definitely seems to still exist...

git-svn-id: https://svn.apache.org/repos/asf/incubator/wave/trunk@1505136 13f79535-47bb-0310-9956-ffa450edef68
Actually remove the waveimport folder (now empty)


git-svn-id: https://svn.apache.org/repos/asf/incubator/wave/trunk@1505138 13f79535-47bb-0310-9956-ffa450edef68