Changements

Reenable reactive behavior in gs-reactor
Store cache in RootContext so that the methods are called on the right
cache, which is not necessarily the one returned by getCurrentCache(). 
When a cache flushes its contents to the disk, call shiftTs on the
caches that registered themselves to get updates so that the
dependencies are updated.
 (commit: c5acbca)

merge
 (commit: 96419de)