Merge branch 'master' into photo-detection

Conflicts:
	pisak/viewer/app.py
	pisak/viewer/widgets.py
refs #770
Merge branch 'master' into photo-detection

Conflicts:
	pisak/viewer/app.py
	pisak/viewer/widgets.py
refs #770
add config reader and stub config
refs #788
Merge branch 'configurator' of ssh://git.nimitz.pl/pisak into configurator
setter for config_path in configurable class
refs #788
take props to change from config not from class
refs #788
add naive multi config application func
refs #788
delete selector props from json in speller, add config to PisakScanningGroup
refs #791
add docstrings to methods
refs #788
add configuratorError error to configurator
refs #788
substitute silent error handling with logging
refs #791
better error handling
refs #788
Merge branch 'master' into configurator