Fix inappropriate uses about eventlet.Timeout
Fix inappropriate uses about eventlet.Timeout

In storlet_runtime.py, there are some codes which generate a Timeout
with string as its argument though Timeout requires timeout value.

Change-Id: Id44a8544a2bc2d49d37d2a86c72f3c1a0a872265

openstack/storlets,openstack/storlets,openstack/storlets,openstack/storlets