Allow editing morphology section types

Sometimes, a given morphology is not annotated correctly and it is therefore necessary to rename some of the branches' section type. If we can have this feature in neuromorphoviz, that would be great. A sample morphology can be found in https://ml-neuronbrowser.janelia.org/ where all dendrites are annotated as basal.

Start by locating the morphology annotation and editing workflow in NeuroMorphoVis, then inspect the sample morphology at https://ml-neuronbrowser.janelia.org/. The work is complete when a user can rename the section type of selected morphology branches, including changing basal dendrites to another type.

Written by the indexing model from the issue text.