[CMake] Enable C++11 for a Target with Intel

[Stephen Kelly]

Robert Maynard wrote:

> Currently the only compilers that support compiler features are:
> 
> Apple Clang versions 4.4 though 6.1.
> GNU compiler versions 4.4 through 5.0 on UNIX and Apple.
> Microsoft Visual Studio versions 2010 through 2015.
> Oracle SolarisStudio version 12.4.
> 
> If you are interested in adding support for the intel compilers you can
> look at:
> Modules/SunPro-CXX-FeatureTests.cmake and
> Modules/GNU-CXX-FeatureTests.cmake
> 

Here's a starting point for someone sufficiently interested:

 https://github.com/steveire/CMake/commit/3f16f927235ebd91603f8314a8

However, I believe the compiler features vary by operating system, so more 
conditions would be needed.

Thanks,

Steve.