0.5.0 Release with breaking changes

NOTE: 0.5.0 includes breaking changes
Official release on PyPI: https://pypi.python.org/pypi/ring/0.5.0/

• Interface
  • BREAKING CHANGE: classmethod as a first-class citizen
    • cls argument will be also coded to key
    • NOTE: @classmethod now must be inside of @ring.func
  • BREAKING CHANGE: CacheInterface's method signatures are changed
  • General action trigger 'run' by @yunitto
    • Any f.run('action') is equivalent to f.action()
    • ex) f.run('execute') is equivalent to f.execute()
  • encode/decode as a member of ring functions by @yunitto
    • f.encode() and f.decode() is connected to the coder.encode and coder.decode
• Backend
  • BREAKING CHANGE: redis backend now depends on aioredis>=1.0.0
    • No backward compatibility in ring
    • No python 3.3/3.4 support
  • diskcache support by @tobark
    • @ring.coder.disk
• Coder
  • Coder registry by @yunitto
    • ring.coder.registry is a default registry
    • registry.register('json', JsonCoder) will add JsonCoder as 'json'
      (which is a built-in code)
  • A new built-in coder: 'pickle' by @jowoojun
• Other
  • ring.func.dict now doesn't hide key prefixes by @LeeChangGun and @Soonmok
  • tuple argument support