Import from Map Layer

[KellyMWhitehead]

A thought occurred to me, there is no real difference between a temporary (scratch) map layer and a map layer in QGiS (just the data source). In fact, to generate the list of temporary map layers, I do a filter on the all the map layers in the project.

So, why not just allow users to import any map layer?

1. would make importing features easier, save mouse clicks of having to navigate to find data if it is already in the map.
2. Allow for selections to limit the data being imported.
3. Allow (or disallow) importing existing qris map layers.
4. Provides a mechanism to import any gis format that QGiS recognizes that we are having trouble with import (e.g. file gdb).

Tasks

1. Test and explore how this works
2. define any filters (i.e. qris layers) or functions (e.g. honor feature selections).
3. Find and fix the sporadic metadata JSON error.