Changed header names to be more consistent

include/FileUtils.h

@@ -1,16 +1,16 @@
-#ifndef FILEUTIL_H
-#define FILEUTIL_H
+#ifndef FILEUTILS_H
+#define FILEUTILS_H
 
 #include <string>
 #include <vector>
 
 using namespace std;
 
-class FileUtil {
+class FileUtils {
     public:
-        FileUtil() = default;
+        FileUtils() = default;
         
-        ~FileUtil() = default;
+        ~FileUtils() = default;
         
         static string getFile(char *path);
         static bool fileExists(char *path);