logic: added Gradle project setup (issue #379)

* added implementation for Gradle project setup (icon is still missing)
* refactored project loading/saving and SourceGroupSettings
* removed long deprecated Cxx UseSourcePathsForHeaderSearch option

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src/lib_cxx/project/SourceGroupCxxCdb.h

@@ -0,0 +1,30 @@
+#ifndef SOURCE_GROUP_CXX_CDB_H
+#define SOURCE_GROUP_CXX_CDB_H
+
+#include <memory>
+#include <set>
+
+#include "project/SourceGroupCxx.h"
+#include "settings/SourceGroupSettingsCxxCdb.h"
+
+class SourceGroupCxxCdb: public SourceGroupCxx
+{
+public:
+	SourceGroupCxxCdb(std::shared_ptr<SourceGroupSettingsCxxCdb> settings);
+	virtual ~SourceGroupCxxCdb();
+
+	virtual SourceGroupType getType() const;
+
+	virtual bool prepareRefresh();
+
+	virtual std::vector<std::shared_ptr<IndexerCommand>> getIndexerCommands(
+		std::set<FilePath>* filesToIndex, bool fullRefresh);
+
+private:
+	virtual std::shared_ptr<SourceGroupSettingsCxx> getSourceGroupSettingsCxx();
+	virtual std::vector<FilePath> getAllSourcePaths() const;
+
+	std::shared_ptr<SourceGroupSettingsCxxCdb> m_settings;
+};
+
+#endif // SOURCE_GROUP_CXX_CDB_H