extend widget test in order to tackle ilastik issue 55
Begin refactoring of export dialog, see #55

The reason for the dialog to take a long time to open was that the
complete (!) data was requested before even creating the dialog
remove usage of deprecated allocate() lazyflow API
fixing exportDialog
fixed Export hanging
updated license
wip: multi step progress dialog
first working version of progress dialog
merged
adding normalizationOptions
tuned exportDialog