Created sub directories of headers to distinguish utils and deprecated
stuff
Introduced BusProcessor and made Crossover an implementation of it
Deprecated BandSummer
Renamed AbstractBusProcessor to BusProcessor as its an interface.
AbstractCrossover and BandsMerger are now BusProcessors.
BandsRmsLimiter now is BusProcessor
Created CharacteristicTimeSetIntegrators, that is a product from a
(Fixed)CharacteristicTimeSet and a sampe rate and used that for the
BandsRmsLimiter.
Added ChannelSummer that sums a number of channels, scales and writes
the result to all output nodes on the bus.
Introduced MultiFilter interface for multi channel filters.
Replaced ArrayVector with FixedSizeArray in various places. Also let
some classes implement MultiFilter or BusProcessor if applicable.