PR #38 breaks valid frozen-lockfile case

[markjm]

@ohana54, it seems #38 breaks a rare, but supported lockfile entry. yarn supports aliasing to other names via the syntax

{
  "package-a": "npm:[email protected]"
}

With the lockfile check in this PR, one of the name field of the original does not match the new lockfile. Because inferredName does not match obj.name, the names mismatch causing deep-equal to fail.