[Qt-creator] [BUG] Release builds are actually debug builds

[Daniel Teske]

> Hi there.
>
> Still building debug instead of release here. My version is:
We don't change your settings. So this is fixed for new projects, or projects 
that have not been opened yet. For projects that you already loaded you can 
change that in the build settings.

> I know this is nothing serious, but just to understand, this happens
> because I "#include" some header on multiple files in my project?
Qmake does that for us, it adds all the necessary include paths to the 
project, and those duplicate entries are not removed. Which as you noted 
doesn't hurt in any way.

daniel