entitlement: bug fixes in DefaultSubscriptionBundleTimeline

This fixes https://github.com/killbill/killbill/issues/149: when
building the TargetState state machine, we weren't considering
some events (e.g. RESUME), resulting in building wrong events for
certain blocking states.

This also fixes a typo in TargetState#addStateAndReturnEventTypes
when returning SERVICE_STATE_CHANGE event types for blocking states
which resumed billing.

Signed-off-by: Pierre-Alexandre Meyer <pierre@ning.com>