0.4.0

added to-chan
added select-step, like reductions but with multiple source signals that each get their own reducing function
flipped argument order of the setup! function passed to splice
added indexed-updates, a signal transformer useful for performing different effects based on which source signal has updated
added reductions function, which works like reducep but has a better name and doesn't do an implicit drop-repeats
removed reducep and transducep
got rid of j.z.i.signal/output-mult
calling core.async's tap function on a live graph created with spawn now supplies you with straight fresh values from the output signal, instead of batches of fresh & cached messages
- this means that values of an output signal can never be nil, since core.async channels don't do nils
added write-port, a signal constructor that lets you treat the returned signal like a write-only core.async channel.

0.3.1

fixed a bug that would throw an error if you tried to use a folding signal like foldp on a signal that emitted multiple values from a single event, e.g. a pipeline with an "expanding" transducer like cat

lift/liftseq renamed to map/mapseq
input signal constructor now also accepts a channel or mult as its value source
new pipeline function lets you transform signals using transducers
extracted some implementation details into impl namespaces
splice function lets you create arbitrary asynchronous signal transformations
a bunch of new functions in the time namespace (timestamp, delay, since, debounce)
impl.signal/signal-mult function to get a particular signal's message mult from a live graph
signals now provide init functions to calculate their initial values whenever a live graph is fired up
various functions which previously required a base value now have lesser-arity forms which inherit the initial value of one of their parent signals
activate-when function is like keep-when, but entirely deactivates unused signals