[Development] Removing the -c++11 option from configure

[Oswald Buddenhagen]

On Sat, Mar 21, 2015 at 11:40:09AM -0700, Thiago Macieira wrote:
> We'd like to make Qt build unconditionally with the latest version of the C++ 
> standard that is supported by the compiler. That implies removing the -c++11 
> option so that the -no-c++11 option goes away too.
> 
> Possible drawbacks:
>  - Inability to test non-C++11 codepaths in the CI
>    => We can add a hidden option for the CI
> 
>  - OS X support without libc++ may go away
>    => I need more information on this
> 
> Advantage:
>  - Will turn on C++14 for recent GCC and Clang
> 
that seems like a total non-sequitur to me.

if you want to enable support c++11+ by default (it isn't yet?), do it,
but why would you *remove* an option?