Handling shared node dependencies in pending edits

[batpad]

Currently, if you create a shared node with a way that has not yet been uploaded to OSM (i.e. still has an observe temporary id), this will create a new node instead of applying it as a shared node when updating both pending edits.

To solve this, we will need to do two things:

• a> establish dependencies -- i.e. mark out that edit with id say observe-xyz cannot be uploaded until observe-abc is uploaded.
• b> whenever a new way is uploaded, retrieve the mapping of ids from OSM when uploading the changeset, look at all pending edits, and replace the temporary OSM IDs with the newly uploaded IDs from OSM.

For a> this would ideally be handled when creating the way in the wayEditHistory screen. For b>, we would need to do something like:

• In the edit-to-osm-change util, return the nodeIdMap that will map the observe- temp ids to the negative IDs we have generated for the changeset upload: https://github.com/developmentseed/observe/blob/edit-ways-changesets/app/utils/edit-to-osm-change.js#L177

• In this uploadOsmChange function in the osm-api service, parse the XML result from OSM and return a mapping of negative ID to the generated OSM ID: https://github.com/developmentseed/observe/blob/edit-ways-changesets/app/services/osm-api.js#L167

• In the upload-edit util, take the nodeIdMap and the mapping of negative IDs to generated OSM IDs, to create a mapping of observe- temp IDs to the generated OSM IDs: https://github.com/developmentseed/observe/blob/edit-ways-changesets/app/utils/upload-edit.js#L33

• From upload-edit return the observe- ID to OSM ID map alongwith the changeset ID: https://github.com/developmentseed/observe/blob/edit-ways-changesets/app/utils/upload-edit.js#L37 - handle this change wherever upload-edit is being called.

• Dispatch an action like NEW_NODE_MAPPING or something with the above mapping: https://github.com/developmentseed/observe/blob/edit-ways-changesets/app/actions/edit.js#L47

• In the reducer, look at all pending edits, and if any of them reference observe- IDs that have been mapped to OSM IDs, update the node ids as well as ndref references to the OSM IDs.

@geohacker - Let me know if this makes sense. I'm not certain of the way to implement the marking out of dependencies to make sure things are not uploaded out of order. This should hopefully just be something like adding a flag when creating a new way that shares nodes with a way that has an observe- id and checking for that flag when uploading (similar to how we do for photos with dependencies on new features, etc.).

[geohacker]

This is fixed in #282