dotcloud/docker — pull request #6992 by mschurenko (2014-07-12 18:54:00+00:00)
Title: include --releasever=/ in mkimage-yum.sh

This script failed when trying to create a docker image based on centos 7. Adding "--releasever=/" fixed it. According to yum man page:

```
Note: You may also want to use the option --releasever=/ when creating the installroot as otherwise the $releasever value is taken from the rpmdb within the installroot (and thus. will be empty, before creation).
```