Javactl

- Renamed `java.env` to `java.prop`.
- Fixed an issue that `java.prop` boolean value was capitalized in the command line.

- Refactored to use OptionParser's `allow_interspersed_args` option and discarded my own implementation.

- Refactored using [mog-commons-python](https://github.com/mogproject/mog-commons-python).
- Added tests.
- Backported logging.handlers for Python 2.6.

- Fixed a bug on unicode characters output.

- Added `log.error.path` setting.
- Added `java.memory.metaspace_min` setting.

- Disabled to print stack trace when an error occurs.