Fedora 27/28 and CentOS vagrant boxes updated - fix for mouse integration issue

[Tirloni, Giovanni]

Hello,

Version '20180723' of these boxes have been released to address an issue in mouse integration and newest versions of VirtualBox and the Linux kernel.

🏆 Huge thanks to Joseph for reporting this issue and working together to find a fix 🏆

If you're running old versions of VirtualBox, it's recommended to update to version 5.2.16. This is what CI is running too.

Boxes have been built/tested with:

    * VirtualBox 5.2.16
    * vagrant 2.1.2
    * Docker 18.06 (new)

You can update them by running these commands:

    $ vagrant box update --box inclusivedesign/centos7
    $ vagrant box update --box inclusivedesign/fedora27
    $ vagrant box update --box inclusivedesign/fedora28

You projects will need to be destroyed and recreated, please make backups if needed (vagrant destroy; vagrant up).

To verify that all your boxes are up to date:

    $ vagrant box outdated --global

To remove old versions automatically:

    $ vagrant box prune

Any help in testing Fedora 28 would be appreciated as Fedora 27 will go out of support soon.

Cheers,
Giovanni