Add some unit tests to Tools

Clean up and test 3 methods from Tools:
- humanReadableFileSize
- isHex
- isBase64

tests/TestTools.h

@@ -0,0 +1,32 @@
+/*
+ *  Copyright (C) 2017 KeePassXC Team <team@keepassxc.org>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 2 or (at your option)
+ *  version 3 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef KEEPASSX_TESTTOOLS_H
+#define KEEPASSX_TESTTOOLS_H
+
+#include "core/Tools.h"
+
+class TestTools : public QObject
+{
+    Q_OBJECT
+private slots:
+    void testHumanReadableFileSize();
+    void testIsHex();
+    void testIsBase64();
+};
+
+#endif // KEEPASSX_TESTTOOLS_H