Create smart linking of like-objects during mannual selection

[acrosman]

Summary
When you manually select objects, often there are some related objects that make sense to recommend as well. Those other objects should be selected by default and a useful message to that effect offered.

Please describe the problem you are trying to solve.
In settings like #104 where we want extra objects because one is selected, we can easily do that during the recommendation process, but if we also want the interface to add those close relations we'll need to do that during manual selection.

Proposed Solution
Create a pattern similar to the current recommendation solution that offers up additional objects during selection. This will need to be disabled and overridden as well. It should be easy to enable or disable on the fly so users can select exactly what they want but get support in being efficient.