Add introspection_numerics header that attempts to abstract platform specific type information into X-Macros
Provide specialisations for struct/union/class detection (for compile-time efficiency) and parameter type (for run-time efficieny) for fundamental types (and pointers/references too)
Added stress tests for Apply, exercised by ArrayTransform on increasingly nested arrays, each of which features types made unique by passing in increasingly higher base integers. Note controlled by macro to enable fast compilation when not trying to stress test Apply