CMake: restrict -std=c++11 option to GNU compiler
CMake: remove debug message
CMake: only process "test" dir if BUILD_TESTING enabled
CMake: add option to enable/disable parser regeneration
parser: enable the 'not' operator with MSVC
deal with missing 'noexcept' in MSVC
deal with lack of support for inherited constructors on MSVC
environment: add missing return statement
CMake: disable unused utility code