Use structured symbolic storage with symbolicStorage/--symbolic-storage

[palinatolmach]

PR #571 by @anvacaru adds support for preserving storage fields in otherwise symbolic storage for contracts during CSE. As discussed today, we can perhaps do the same thing when making contracts' storage symbolic during the execution; it is currently done via symbolicStorage(address) cheatcode, but it might be easier to do through introducing a CLI argument --symbolic-storage — that would probably mean that all contracts getting deployed during the execution would have symbolic storage by default.

That would make constraints more compact and readable as that'll substitute, e.g., SF_C:Int instead of #lookup ( CONTRACT_STORAGE:Map , 0 ), which might bring usability and performance improvements. That would, however, require extending support for more storage field types than is present in #571.