v0.8.0

• Added try and catch.
  • These are demonstrated by the sample code in try.lisp.
• Rewrote argument handling to allow variadic arguments for macros.
  • Using this (cond) became possible to implement correctly.
  • Moved (cond) from being implemented in golang, to being a Lisp macro.
• Added new macros (when), (if2), etc.
• Added more test-cases.
• Added (count) as an alias to (length)
  • Useful for Mal compatibility.
• Added (strlen).
• Added (ms), similar to (now) but with smaller units.