Rewrite

New features

• added lazy-seq as a dependency, and made all sequence functions use it
• added itable as a dependency, and made all tables immutable by default
• implemented transducers
• implemented transients
• added ns macro

Changes

• fn* no longer splits multisyms and doesn't bind both local and namespaced versions
• fn* is for anonymous functions, it doesn't create a local binding
• def now binds in terms of the namespace, specified by ns
• def no longer support documentation metadata

Removed features

• removed ordered-set and ordered-map
• into is no longer a macro
• empty is no longer a macro
• removed metadata-related macros

Fixes

• #1 (closed) has been fixed, and fn* now generates multi-value destructuring when possible.