proposing new function to GostNets

[d3netxer]

When doing a pandana_snap, there can be situations where multiple origin points snap to the same point on the graph.

This can make it difficult if you want to include the time from the origin node to the nearest node in the graph as part of your OD matrix calculation.

This proposed function would be run after pandana_snap but before calculate_OD, if it is desired. The function would create new edges between the origin points and their nearest nodes on the graph. The edges would have a costs associated with a specified distance or time (most likely walking time).

function name: sprout_graph()

note: Also, since we use Multidigraphs, there would be two edges added per connection from origin node to nearest node.