Fix several issues in the preprocessor:

- macro expansion of hexidecimal numbers 
 - give errors instead of warnings/silence on extra tokens after #endif, #else, etc.
 - give errors on reserved macro name use, reuse of argument, and redefinition with different whitespace presence
 - detect and give error for all cases of #elif and #else after #else



git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@23982 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/cppComplexExpr.vert

@@ -46,3 +46,6 @@ float foo()
     return ADD(gl_Position.xyxwx, 3.0)  // ERROR, should be this line number
     return ADD(gl_Position.y, 3.0)
 }
+
+#if 0
+// ERROR, EOF