LESS import cleanup

* Remove duplicate import
* lightbulb.postEdit was importing lightbulb.common, even though
  that is an output module, not a library, and it was already
  depending on it.  Replace the import with an import of the variable
  module, since that was previously how @colorGray15 was indirectly
  imported.

Change-Id: I9862afac4bab196ba3fe1523770329627e9b441a
Merge "LESS import cleanup"