logic: source groups for project settings

* project can not have multiple source groups with different types
* language of a project is now inferred from source groups
* setting global NameHierarchy delimiter of first sourceGroup in project
* added project settings migrations for source groups
* Add Settings Migration classes (MoveKey, DeleteKey, Lambda)
* Update sample projects with migrations
* added method to config to retrieve sublevel key names
* implemented recursive removing of keys in settings
* moved project files out of top level
* removed solution parsing code as it is not used anymore

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src/lib/settings/migration/MigrationMoveKey.h

@@ -0,0 +1,17 @@
+#ifndef MIGRATION_MOVE_KEY_H
+#define MIGRATION_MOVE_KEY_H
+
+#include "settings/migration/Migration.h"
+
+class MigrationMoveKey: public Migration
+{
+public:
+	MigrationMoveKey(const std::string& oldKey, const std::string& newKey);
+	virtual void apply(Settings* settings) const;
+
+private:
+	const std::string m_oldKey;
+	const std::string m_newKey;
+};
+
+#endif // MIGRATION_MOVE_KEY_H