New implementation of avocado.utils.archive.

This is a new implementation of avocado.utils.archive,
built upon Python stdlib zipfile and tarfile modules,
with a class that creates zip files or tarballs based on the filename
and a few helper functions, to create and extract compressed files.

Signed-off-by: Ruda Moura <rmoura@redhat.com>
selftests/unit: Add new archive module unittests

Verify the functionality of each new API wrapped.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #106 from lmr/ruda-new_archive_module

New archive module