Implement synchronous playlist
Asynchronous playing with control over the position
Tidy up refactoring
Shuffle functions in core.clj
Change byte-seq to use generators
Simplify source-generator

The usage of an atom to protect from creating input-streams is horrible.
Reimplemnt send-context in terms of generators
Remove the current-source concept
Implement MutableList
Integrate shout.playlist with core

This includes simplifying and fixing the logic in MutableList's cons
DRY creating an empty mutable list
Improve doc
Rename function with verb
Fix cyclic dep
Make input-stream-generator own the input-stream
Add support for asynchronoulsy streaming a mutable playlist