New CentOS 7 and Fedora 26 vagrant boxes

[Tirloni, Giovanni]

Hello,

   Boxes have been updated with newer packages and some fixes, please ensure you have the latest version:

$ vagrant box update --box inclusivedesign/centos7   # v20171004
$ vagrant box update --box inclusivedesign/fedora26  # v20171020

   To verify that all your boxes are up to date:

$ vagrant box outdated --global

   To remove old versions automatically:

$ vagrant box prune

Regards,
Giovanni