As we rollback the cache modification when loading a module, we must clear all
of them at the end to ensure to not keep outdated data.
issue9759
review339421002
On distributed setup, the cache is not synchronized instantaneously so we can
not use the cache if the record was modified by another process since the last
synchronisation.
issue9013
review262841002
We implement sync, commit and rollback to follow transaction semantic.
When a transaction clears a cache, the global cache is cleared only when the
transaction is committed meanwhile the transaction will use a cache for itself
only.
We remove _nocache option because the sync, commit and rollback operate only
for the transaction.
issue7975
review53521002
Cédric Krier