Implemented follow-symlinks feature for S3.

Added unit and integration tests along with PEP8 reformatting for
the entire file.
Added --[no]-follow-symlinks options.
Removed quietly skipping over bad symlinks.
Merge branch 'kyleknap-sym_dev' into develop

* kyleknap-sym_dev:
  Removed quietly skipping over bad symlinks.
  Added --[no]-follow-symlinks options.
  Implemented follow-symlinks feature for S3.
Update changelog with latest changes