Revise include order using clang-format-6.0

Run the `clang-format.bash` script to update our C and C++ code to a new
include order `.clang-format`.  Use `clang-format` version 6.0.

Tests/ExternalProjectLocal/Step5/MathFunctions/mysqrt.cxx

@@ -1,12 +1,13 @@
-#include "MathFunctions.h"
-#include "TutorialConfig.h"
 #include <stdio.h>
 
-// include the generated table
-#include "Table.h"
+#include "MathFunctions.h"
+#include "TutorialConfig.h"
 
+// include the generated table
 #include <math.h>
 
+#include "Table.h"
+
 // a hack square root calculation using simple operations
 double mysqrt(double x)
 {

Tests/ExternalProjectLocal/Step5/tutorial.cxx

@@ -1,9 +1,10 @@
 // A simple program that computes the square root of a number
-#include "TutorialConfig.h"
 #include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "TutorialConfig.h"
+
 #ifdef USE_MYMATH
 #  include "MathFunctions.h"
 #endif