Review Qt5 builds on common Linux distributions

[frankosterfeld]

So far we stuck to Qt4 on Linux because Qt5 had issues on Linux desktops, especially when it comes to window management/systray integration (misplaced icon on Unity, for example). We should check if that's still the case with the most common Linux distributions (check what KDAB people use these days) or if we can move to Qt5 for Linux packages.

So we should

• collect who uses which distribution and desktop environment
• Check the status of Charm/Qt5 on these distros/environments

To test we could either use VMs (might be a bit time-consuming to set up) or ask a developer for each important setup to build and test Charm against the Qt5 packages shipped by his distro.

[mgiroday]

Sent a mail to dev about this matter.