Hopac 0.0.0.45

Added basic `Stream.buffer` combinator. Renamed `Stream.subscribe*` to `Stream.consume*` to better describe semantics. Doc refinements. Added `Stream.pullOn`, `Stream.skipWhileJob`, `Stream.skipWhileFun`, `Stream.pullOn`, `Stream.foldBack`, `Stream.mapIgnore`, `Stream.ambAll`, `Stream.appendAll`, `Stream.mergeAll` and `Stream.switchAll` Fixed to start reading the serialized variable immediately as documented. Added `Stream.subscribe*` as a shorthand for `Stream.iter* |> queue`. Added mutable `Stream.Property<'x>` that generates property change notifications for e.g. WPF data binding. Added `doFinalizeJob` and `doFinalizeFun`. Experimental wrapper for streams that tracks space safety via phantom types. Changed `groupByJob` and `groupByFun` to take an additional function/job for forming new groups. Added `Stream.tailsMapFun` and `Stream.initsMapFun` these are useful for lifting the `Stream.tails` and `Stream.inits` functions. Added `keepFollowing1` and renamed `keepLatest` to `keepPreceding` to make the naming more symmetric although the concepts of "following" and "preceding" aren't really fully symmetric (unless you allow time travel). A slightly more performant implementation of `keepLatestFuns`. Renamed from `lazify` to `keepLatest`. Lazification of live streams. Rethinking timing and throttling operations. Generalized `joinWith` and `mapJoin`. There is no sleep, only `timeOut`. Added ability to directly bind observables in job computation expressions. Removed superfluous methods from `Async.OnWithSchedulerBuilder`.