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/settings/Settings.cpp

@@ -118,9 +118,9 @@ std::vector<FilePath> Settings::getPathValues(const std::string& key) const
 	values = getValues(key, values);
 
 	std::vector<FilePath> paths;
-	for (const std::string& path : values)
+	for (const std::string& value : values)
 	{
-		paths.push_back(FilePath(path));
+		paths.push_back(FilePath(value));
 	}
 	return paths;
 }