Automatically narrow down dependencies given as "any" (#675)

Automatically narrow down dependencies given as "any" (#675)

* Implement narrowing down of new "any" dependencies

Instead of adding just a foo* dependency, check how it was solved and use that
version to add a more precise (and usually wanted) dependency; e.g., foo^1.2,
foo~0.1

* Fix case of dependency removal

* New test and fixed other tests to new behavior

Many tests explicitly check the added dependencies, so this is extra assurance
about this change.

* Recognize the wildcard as "any" version

* Document user-visible changes

* Add option to disable new behavior