Added swift-account-info tool.

This is a very simple swift tool to retrieve information
of an account that is located on the storage node.
One can call the tool with a given account db file
as it is stored on the storage node system.
It will then return several information about that account.

Change-Id: Ibfeee790adc000fc177b4b3c03d22ff785fda325
Merge "Added swift-account-info tool."