Config UI: Add detail to init/prepare stage names

The advanced config backend generates descriptive
names for main stages today, but not for the init
and prepare stages. This patch adds the missing
detail (object size, #containers, #objects,
as well.

This addresses issue#186

Signed-off-by: Khushbu Shrivastava <khushbu.shrivastava@intel.com>
Config UI: Clean up prepare stage generation code

Addresses issue#186

Signed-off-by: Khushbu Shrivastava <khushbu.shrivastava@intel.com>