[analyzer] This patch removes passing around of const-invalidation vs regular-invalidation info by passing around a datastructure that maps regions and symbols to the type of invalidation they experience. This simplifies the code and would allow to associate more different invalidation types in the future.
With this patch things like preserving contents of regions (either hi- or low-level ones) or processing of the only top-level region can be implemented easily without passing around extra parameters.

This patch is a first step towards adequate modeling of memcpy() by the CStringChecker checker and towards eliminating of majority of false-positives produced by the NewDeleteLeaks checker.