Changelog for elerea-2.4.0

2.4.0 - 111111 * added effectful signals to assist library writers 2.3.0 - 110627 * reimplemented clocked variant in a correct and more efficient way 2.2.0 - 110402 * added n-ary transfer functions * temporarily removed transfer from the clocked variant * revised documentation 2.1.0 - 100805 * reimplemented the parametric variant in a way that doesn't require signals to carry the type of the parameter any more * added the ability to extract the global input in the parametric variant, and also to override it (input and embed, resp.) * added until to be able to define switchers that can truly drop references to old signals * added debug printing capability to the simple and clocked variants * made a note about possibly deprecating the delayed variant 2.0.0 - 100718 * moved experimental branch to the top (version 1 went into legacy status) * added the clocked variant 1.2.3 - 100131 * added externalMulti to handle events that can fire several times within a superstep * added a cache to the noise signal for safety reasons, so it lives in SignalGen now 1.2.2 - 100115 * added noise signals and the getRandom primitive (using mersenne-random) 1.2.1 - 091204 * modified the &&@ and ||@ operators to short-circuit 1.2.0 - 091202 * added the delayed variant to the experimental branch * renamed storeJust to (-->) in the experimental branch 1.1.0 - 091126 * added experimental branch with a cleaner semantics 1.0.0 - 090726 * completely renewed interface by introducing the SignalMonad 0.6.0 - 090507 * renamed Void to StartToken * replaced restarter with the simpler and more versatile startTokens 0.5.0 - 090502 * changed names of internal constructors to match primitives better * added restarter and (==>) * removed the unused type synonym Time 0.4.0 - 090501 * added keepAlive * made delay a primitive * completely separated sampling and aging 0.3.0 - 090419 * documentation bug fixed: the latcher is not delayed * added dot (Graphviz) converter 0.2.0 - 090412 * removed primitives time and stateless * removed default delay on stateful combinators and added experimental cycle detection * added some non-primitive combinators: delay, edge, comparisons, logic relations * added signal instances for various numeric classes 0.1.0 - 090410 * first public version