GEE C++ code should be build-able without the use of gnu extensions

[tst-rwildes]

Currently the std parameter to the compiler needs to be std=gnu++98 or soon will need to be std=gnu++11 (see #774). GEE code should compile without the need of gnu extensions. If the gnu extensions are needed for a third party library to build and there isn't a newer version or an alternate library we can use then we should isolate the need for the gnu extensions to only that library (and maybe a small wrapper library) and this requirement should not 'bleed over' to the rest of the code base so as much code as possible can build without gun extensions.

[tst-lsavoie]

@tst-rwildes can this be closed? It has a PR. The only place I see gnu++ still being used is in the portable build.