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/project/SourceGroup.cpp

@@ -0,0 +1,41 @@
+#include "project/SourceGroup.h"
+
+SourceGroup::~SourceGroup()
+{
+}
+
+LanguageType SourceGroup::getLanguage() const
+{
+	return getLanguageTypeForSourceGroupType(getType());
+}
+
+bool SourceGroup::prepareRefresh()
+{
+	return true;
+}
+
+bool SourceGroup::prepareIndexing()
+{
+	return true;
+}
+
+void SourceGroup::fetchSourceFilePathsToIndex(const std::set<FilePath>& staticSourceFilePaths)
+{
+	for (const FilePath& sourceFilePath: m_allSourceFilePaths)
+	{
+		if (staticSourceFilePaths.find(sourceFilePath) == staticSourceFilePaths.end())
+		{
+			m_sourceFilePathsToIndex.insert(sourceFilePath);
+		}
+	}
+}
+
+std::set<FilePath> SourceGroup::getAllSourceFilePaths() const
+{
+	return m_allSourceFilePaths;
+}
+
+std::set<FilePath> SourceGroup::getSourceFilePathsToIndex() const
+{
+	return m_sourceFilePathsToIndex;
+}