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/data/TaskCleanStorage.h

@@ -16,8 +16,7 @@ class TaskCleanStorage
 public:
 	TaskCleanStorage(
 		PersistentStorage* storage,
-		const std::vector<FilePath>& filePaths,
-		std::shared_ptr<DialogView> dialogView
+		const std::vector<FilePath>& filePaths
 	);
 
 private:
@@ -28,7 +27,6 @@ private:
 
 	PersistentStorage* m_storage;
 	std::vector<FilePath> m_filePaths;
-	std::shared_ptr<DialogView> m_dialogView;
 
 	TimePoint m_start;
 };