Molinillo shows already-resolved conflicts in the VersionConflict exception.

Error message:

```
Bundler could not find compatible versions for gem "does-not-exist":
In Gemfile:
dep2 was resolved to 0.0.1, which depends on
does-not-exist (= 1.0.0)

Could not find gem 'does-not-exist (= 1.0.0)', which is required by gem 'dep2', in any of the sources.

Bundler could not find compatible versions for gem "librato-metrics":
In Gemfile:
librato-metrics (= 1.5.0)

dependency was resolved to 0.0.1, which depends on
librato-metrics
```

Clearly, there's no real conflict with `librato-metrics`. If you fix the `does-not-exist` dependency error, then the `librato-metrics` error goes away. I traced the problem to the version of Milinillo that's in the Bundler repo, but that bug probably exists here too.

This small project demonstrates the problem: https://github.com/j3pic/bundler-test

Start by running the linked bundler-test reproduction and reviewing the Molinillo version used in the Bundler repository. Trace how VersionConflict formats conflicts when the missing does-not-exist dependency remains unresolved, then verify that the already-resolved librato-metrics conflict no longer appears after the underlying error is fixed.

Written by the indexing model from the issue text.