New annotation for network junctions shapefiles

Jianfei brought to my attention the fact that it is very hard to find out what junctions correspond to what on the graph he is making.

So what I am going to do is go through and manually annotate the network junction file to indicate what the junction is. The labeling schema will be similar to this:

Elevators : E###
Stairways: S###
Exit/Entrance: M###
Room: R###(alpha)
Everything Else (null): N###

This should make it a bit easier to interprete when he goes in and creates this floor centerline graph. I also added support for Z-coordinates and a spatial index on these new shapefiles.