Bump up online installer version from 1.4 -> 1.5

Change-Id: I6b4ece094c08a532ef2296170f9a10fe44512e2f
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>
Adding EXTRA_QT_CONFIGURATION also for desktop builds

Passing extra parameters for desktop builds also needed.

Change-Id: I365d40fd7df75c8bd4a639f788fdf1b60e97b1a5
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>