Merge branch 'master' into develop
Merge branch 'develop' into feat-authentication
Add dblclick to select node.
Make nodes removable.
Update curate ui.
Update sidepanel ui.
Update node editing form.
Add function to insert node.
Add bounding boxes.
Cleaned up insert node function.

Still retain known issue where inserting a node breaks d3.
Merge branch 'feat-authentication' into develop
Merge branch 'develop' into feat-curate
Fixed edit path.

Insert path remains broken.
Add svg download.
Move path style from css to svg.

This makes the download svg function work, because the styles of the
drawing are stored locally.
Cleaned up svg defs declarations in d3.
Added gradient background.
Merge branch 'feat-curate' into develop
Cleaned up alignment.
Merge branch 'feat-header' into develop