Support tar files in repo with pkglist = [ "all" ]

[skwsk]

The current code doesn't work well with tar files in repo directory:

1. If pkglist has list of tar file name, it has a few issues including issue #22 and #23
2. If pkglist is empty, only rpm files in repo directory are used, ignore tar files
3. If pkglist = [ 'all' ], the GISO built without any SMUs in tar files.

This PR fixed for 3rd one (Fix #25). With this code change, if tar files in repo directory and pkglist = [ 'all' ], GISO created successfully. Key changes:

• Too many wrongly nested loop for repo_paths
• filepath for tar file is wrong, directory path added to the full path of tar file incorrectly
• repo_files should be initialized only at start of validate_and_return_list()

And additional minor fix included to fix log message related with third party SMU (same as PR#10)