Namespace console.log before it is passed to runCode

https://github.com/gajus/isomorphic-webpack/blob/4eb08335b1affdbbae8ae481875d10810e162543/src/utilities/runCode.js#L13

Use a namespace for all messages being logged in a VM. Otherwise, there is no way telling whether the logs are coming from the main code or the VM code.

Start by reading src/utilities/runCode.js at line 13 and trace how console.log is passed into the VM. Add the requested namespace to VM log messages, then verify that output distinguishes VM logs from main-code logs.

Written by the indexing model from the issue text.