Added filtering of directories

 * Any path that doesn't represent a file is now omitted from the
   report.
 * Syntax of moved or copied paths no longer causes errors however
   the script still doesn't handle them as well as they could.
   In the long run copied files should include their source in
   the destination's revision list and should not include the
   source path in the report.

Signed-off-by: Nathan Callister <ncallister@iwsoftware.com.au>