Refactored calamares_bin into calamares_bin and libcalamaresui.

Now linking with -Wl,--no-undefined!
Moved find_package KF5 from the root CMakeLists.txt to the partitioning
module where it belongs. KF5 deps should be limited to plugins.
Lots of random fixage to make stuff link.
Removed CalamaresApplication reference from Settings.
Removed the use of AbstractPage, we don't need it right now.

src/libcalamaresui/Settings.h

@@ -0,0 +1,57 @@
+/* === This file is part of Calamares - <http://github.com/calamares> ===
+ *
+ *   Copyright 2014, Teo Mrnjavac <teo@kde.org>
+ *
+ *   Calamares 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   Calamares 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 Calamares. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef SETTINGS_H
+#define SETTINGS_H
+
+#include "UiDllMacro.h"
+
+#include <QObject>
+#include <QStringList>
+
+
+namespace Calamares
+{
+
+class UIDLLEXPORT Settings : public QObject
+{
+    Q_OBJECT
+public:
+    explicit Settings( bool debugMode, QObject *parent = nullptr );
+
+    static Settings* instance();
+    //TODO: load from JSON then emit ready
+
+    QStringList modulesSearchPaths();
+
+    QStringList viewModulesPrepare();
+
+    QStringList viewModulesPostInstall();
+
+
+private:
+    static Settings* s_instance;
+
+    QStringList m_modulesSearchPaths;
+    QStringList m_viewModulesPrepareList;
+    QStringList m_viewModulesPostInstallList;
+};
+
+}
+
+#endif // SETTINGS_H