Fixes Issue #19

This references the initial file base path instead of redeclaring it. 

I'm really not clear as to why `base: path.dirname(file.path),` was used to declare this previously, unless it is desired to keep all the files in single tier directory after compilation. Inheriting the previous directory structure makes a lot of sense for a lot of people because it can prevent filename collisions.

If this is unacceptable, perhaps an option should be added so that the user can override the default behavior if desired.