* 0.5
  - This version is incompatible with the 0.4 or less.
  - Split the file.
  - Added pythonbrew-install script.
  - Added pybrew script. This is a symbolic pythonbrew.
  - Rename `search` to `list`.
  - Removed `init`.
  - Added syntax that `pythonbrew command <VERSION>`
  - Change default PYTHONBREW_ROOT path as $HOME/.pythonbrew