TangoAttribute calls .disablePolling() when
unsubscribing from Change events (this happens automatically
e.g. when removing its last listener). This is problematic
because it permanently disables the polling (e.g. it
won't e re-activated if a listener is lately added to the
same attribute). Prevent this by "deactivating" instead of
"disabling" the polling.
TangoAttribute calls
.disablePolling()when unsubscribing from Change events (this happens automatically e.g. when removing its last listener). This is problematic because it permanently disables the polling (e.g. it won't e re-activated if a listener is lately added to the same attribute). Prevent this by "deactivating" instead of "disabling" the polling.Fixes #1113