Eval script sending wrong query

The eval script sent the name of the language at the end of the hashbang of the generated script, not the command as it seems like it should. (i.e. it was sending `#!/usr/bin/py3` instead of `#!/usr/bin/python3.4`). This pull request takes care of that. It works at least with the pythons and bash, I haven't tested others.

This is likely a fix for #1384