Tests on maps and lists may not actually be testing much

[tcharding]

If an RPC call returns a list or map and in the integration test the returned list/map is empty then the test is not actually testing that much.

In a perfect world we would ensure every vector and map in the lib is populated in a test - this is probably too much work. We could at least check every type that is a simple wrapper around a map/list and check it is not empty.

For an example see getindexinfo.