Store the initial object dict for future use
New utility function sliced() for cutting loafs
Status can be specified upon test case creation
Cache.update() support for multicall slicing

The update is done in batches. The max number of objects
updated at once is controlled by the global variable
MULTICALL_MAX, by default set to 10 objects per session.
Internal utility function for idifying
Improved logging for Container add/remove methods
Support for test case sortkey in test plans [BZ#869594]

New classes CasePlan and PlanCasePlans implemented
Method TestPlan.sortkey() for getting/setting the order
Typo in cache level detection