Rating system designed to be used in VoIP Carriers World.

Features
* Fast RatingEngine, holds all rating information into memory
* Unlimited spanned timebased rating: considers both ActiveFrom/RateStartsAt
* Unlimited rate profiles chanining for fallback
* Rating Fields: ConnectFee, RateIn, RateOut
* High accuracy rating: configurable to miliseconds
* Flexible rates storage - plugin based rates loading