Compatibility fixes for switch from global AttrDict to AttrTree

The global measurement AttrDict is now switched to an AttrTree.
Since AttrTree only supports uppercase labels for its children
all lower case children had to be renamed. This includes maps,
curves, cfs, rfs, and the _activity_buffer, which are now
called Maps, Curves, CFs, RFs and ActivityBuffer.
Updated dataviews submodule reference
Fix to measurement ProgressBar for empty measurements