fix VS2012 compile issues

small fixes needed to compile under Win8.1/VS2012/static_lib

glslang/Include/Common.h

@@ -67,6 +67,7 @@ std::string to_string(const T& val) {
 #endif
 
 #if defined(_MSC_VER) && _MSC_VER < 1800
+	#include <stdlib.h>
 	inline long long int strtoll (const char* str, char** endptr, int base)
 	{
 	  return _strtoi64(str, endptr, base);

glslang/MachineIndependent/Intermediate.cpp

@@ -47,6 +47,7 @@
 
 #include <cfloat>
 #include <utility>
+#include <tuple>
 
 namespace glslang {