Read Neurolucida branch termination type from DAT files

[bmihaljevic]

Neurolucida files can have "Normal", "Incomplete", etc. markers for terminal branches (https://www.mbfbioscience.com/help/nx11/Content/Analyses/Dendrogram_Analysis.htm). Currently we are only reading such information for Neurolucida ASC files, not for DAT ones.