moved the DEBUG flag into QSettings
got the Data Log mostly implemented. There's a fatal error caused by the request, though. Likely a multi-threading issue.
several changes

- fixed race condition between the data log and instruments (CurrentDataLogFile)
- added some logging
- only the Recent Data plot is now auto ranged
- improved variable name consistency
- fixed logging of the GUI thread
several changes

- added more logging
- fixed DataLogViewController._buffer not being deleted on deactivation
- simplified DataView's implementation
- fixed auto range (for real this time)