drop unused nonstandard require
More concrete explanation of markBottom vs markTop
typo fix
(Some dots do go inside parens.)
Restore a comment I found helpful.
Remove unused cp_r preserveMode option

I had originally created a commit which let preserveMode reuse the
return value of the fs.statSync a few lines up in the file, but since
the code is dead, there was no way to test it. Removing the dead code
seemed like a better approach.  (If you want to revert this commit, I
recommend reusing the stat buffer!)
Use utils.randomToken in meteor-npm.js
Sort of explain why an error shouldn't happen
Remove unused require from main