For new cloudrons this will first remove the previously added group and
mailbox entry from the db migration scripts and readds it once we have a
domain on owner creation
We use only mysql, so updating this means a lot of unused db backends
like sqlite do not need to be built with gyp anymore.
Note that this version is not yet released as stable, but works fine for
us. The outstanding issues are not related to our use-case from what I
can tell.
Fixes#82
