Remove unused timeout arg to ResultsReporter init

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Add a requests.Session object to ResultsReporter

By default it is set up to retry requests 10 times

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Use the new ResultsReporter.session object

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Drop usage of safe_while

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Merge pull request #247 from ceph/requests-sessions

Use a requests.Session object for retries instead of safe_while