client: workaround socket leak

client: workaround socket leak

Recreate the boto connection object after every 512 requests in an
attempt to workaround a socket leak when the remote end closes the
connection. Boto does not seem to be causing httplib to close() the
sockets appropriately in some cases. I'm not sure exactly where
the leak is occurring, but forcing boto to reinitialize its
connection pool like this avoids it.

Signed-off-by: Josh Durgin <jdurgin@redhat.com>