bump of Qt version to 5.9

[Timothée Giet]

Le 13/12/2018 à 08:42, Johnny Jazeix a écrit :
> Hi,
>
> I was planning, after the release, to bump the minimal version of 
> required Qt to 5.9 as Qt5.6 LTS finishes in March. This way, it would 
> allow us to use QtQuick.Controls2 (which were added in 5.7) and 
> potentially improve the memory usage.
>
> Does someone see an issue to bump the version? (maybe not available in 
> some distributions...?)
>
> Johnny


Hi,

After checking on distrowatch, looks like most distributions ship at 
least 5.7, with current Debian stable using 5.7.1.
So, while using 5.9 is better in practice, maybe we can just bump 
minimal required version to 5.7 as long as we don't actually require 
anything from 5.9.

Timo.