Build for Electron 11 on MacOS fails

[sergei-dyshel]

In file included from ../src/language.cc:1:
In file included from ../src/./language.h:4:
In file included from ../node_modules/nan/nan.h:56:
In file included from /Users/sergei/Library/Caches/node-gyp/11.3.0/include/node/node.h:67:
In file included from /Users/sergei/Library/Caches/node-gyp/11.3.0/include/node/v8.h:30:
/Users/sergei/Library/Caches/node-gyp/11.3.0/include/node/v8-internal.h:418:38: error: no
      template named 'remove_cv_t' in namespace 'std'; did you mean 'remove_cv'?
            !std::is_same<Data, std::remove_cv_t<T>>::value>::Perform(data);
                                ~~~~~^~~~~~~~~~~
                                     remove_cv
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/type_traits:665:50: note:
      'remove_cv' declared here
template <class _Tp> struct _LIBCPP_TEMPLATE_VIS remove_cv
                                                 ^

According to electron/electron#26364 the code needs to be compiled in C++14 mode to fix that.