Prevent blocking of server when multiple changes are made to document in short time interval

[vetlek]

Currently all change events to documents are queued and all are executed even tough there might be newer changes in to document. This makes the extension unresponsive for large config files. Should investigate how this is handled by other extensions. Possible solution: Stackoverflow

[vetlek]

The correct solution is probably to create a dedicated server for parsing of septic files and potentially other tasks that are long running. This will free up the event handler to process new events while the tasks are run and support the possibility of using cancellation tokens when more up to date tasks arrives.