Time to Upgrade Qt5

[Amit Yaron]

Unfortunately, tools such as VLC and VirtualBox don't tell us when it's 
time to upgrade Qt5.
I found it today after I'd upgraded VirtualBox and got messages such as:

    VirtualBox: supR3HardenedMainGetTrustedMain:
    dlopen("/usr/local/lib/virtualbox/VirtualBox.so",) failed:
    /usr/local/lib/virtualbox/VirtualBox.so: Undefined symbol
    "_ZNK6QColor6darkerEi at Qt_5"

Having checked how up-to-date is Qt5 using:

    pkg version

and upgraded some packages, now both tools work fine.

So, I believe it should be added to the post-install notifications and 
the output of "pkg desc".