logic: multithreaded parsing

* modified the TaskParseCxx to be able to run multiple times in parallel
* made FileRegister threadsafe and changed a lot of its mechanisms
* added TaskGroupParallel that runs all children in parallel
* added TaskParseWrapper that acts as a decorator to execute some code before and after parsing.
* implemented task setup in project with 4 parsing threads
* removed SimpleTask as it was only used as interface for the LambdaTask

src/lib/data/parser/ParserClientImpl.cpp

@@ -25,12 +25,12 @@ void ParserClientImpl::resetStorage()
 	m_storage.reset();
 }
 
-void ParserClientImpl::startParsingFile(const FilePath& filePath)
+void ParserClientImpl::startParsingFile()
 {
-	m_nodeIdsToMemberEdgeIds.clear();
+	m_nodeIdsToMemberEdgeIds.clear(); // remove this when one parserclient is created per file
 }
 
-void ParserClientImpl::finishParsingFile(const FilePath& filePath)
+void ParserClientImpl::finishParsingFile()
 {
 }