some formatting changes
initial attempt at implementing an eventlet-based local file downloader
docstrings and formatting
fixed bug that sets mex_concurrent to None when max_concurrent is not provided
initial unit tests, more to come
got rid of fancy eventlet concurrency, regular os operations are faster; fixed bug where the report state was never started
rest of local downloader unit tests
Merge branch 'master' into jconnor-local-file-downloader
Merge branch 'master' into jconnor-local-file-downloader
suggestions from PR review
Merge pull request #6 from pulp/jconnor-local-file-downloader

Jconnor local file downloader