Fix compile with newer Qt 5.

That includes less headers implicitly, so we need
to list them explictily ourselves.

src/autotests/CharacterColorTest.h

@@ -20,6 +20,8 @@
 #ifndef CHARACTERCOLORTEST_H
 #define CHARACTERCOLORTEST_H
 
+#include <QObject>
+
 #include "../CharacterColor.h"
 
 namespace Konsole

src/autotests/ShellCommandTest.h

@@ -21,6 +21,8 @@
 #ifndef SHELLCOMMANDTEST_H
 #define SHELLCOMMANDTEST_H
 
+#include <QObject>
+
 #include "../ShellCommand.h"
 
 namespace Konsole

src/autotests/TerminalCharacterDecoderTest.h

@@ -20,6 +20,8 @@
 #ifndef TERMINALCHARACTERDECODERTEST_H
 #define TERMINALCHARACTERDECODERTEST_H
 
+#include <QObject>
+
 #include "../TerminalCharacterDecoder.h"
 
 namespace Konsole