First draft of updates for where_used feature.

Signed-off-by: Paul Osborne <paul.osborne@spectrumdsi.com>
Fixes after initial testing.

Signed-off-by: Paul Osborne <paul.osborne@spectrumdsi.com>
Fixes from testing and new example file.

Signed-off-by: Paul Osborne <paul.osborne@spectrumdsi.com>
Issue 14: Incporporate support for file retrieval & where_used query
Merge remote-tracking branch 'origin/master'
Merge https://github.com/posborne/Anvil