reorder files, in preparation for Bullet 3 -> Bullet 2 merge

Demos3/Wavefront/string_extra.cpp

@@ -0,0 +1,16 @@
+#include "string_extra.h"
+#include <string.h>
+
+char strequal(const char *s1, const char *s2)
+{
+	if(strcmp(s1, s2) == 0)
+		return 1;
+	return 0;
+}
+
+char contains(const char *haystack, const char *needle)
+{
+	if(strstr(haystack, needle) == NULL)
+		return 0;
+	return 1;
+}