Fixed field tag reference processor.
Added monitord development command-line options.
Properly handle null values on import.
Updated datastream tags.
Downsample streams in maintenance processor.
Extended TagReference to support string formatting.
Merge branch 'development' of github.com:wlanslovenija/nodewatcher into development
Merge branch 'development' of github.com:wlanslovenija/nodewatcher into development
PEP8 style fixes.