Tea-test-994699

- Added TeaError as a base class for all submodule errors.


---

- Make singleton initialization thread safe.


---

- Module cleanup. Remove all unused modules.
- Remove support for python2 and IronPython.
- Remove unnecessary windows specific modules.
- License change from BSD to Apache-2.0.
- Added timestamp module.
- Process module enhanced.
- Fixes for python3.


---

- Change project organization.
- Remove tornado JsonHandler. It is too application specific to be in a
common library such as tea.
- `environment` parameter in the `process` module changed to `env`.
Creation of full environment moved to the base `Process` class.
- Adding `working_dir` parameter to the `Process` class constructor.
- Rename tea.shutil to tea.shell
- Added `tea.shell.gremove`
- Added `ctx` - context manager library
- Added `tea.utils.load_subclasses`
- Remove the `tea.cron` module. The same thing can be found in the
`APScheduler` python package on PyPI.
- Add `tea.shell.touch` and hide helper functions in `tea.shell`.


---

- Porting everything to work with Python 2.7 and Python 3.3.
- Adding `six` library to `utils` module.
- Adding `docstring` decorator.
- Refactoring the `process` module. Removing duplicate functions and merging
all `execute_` functions to a single `execute`.


---

- Fix in the `tea.process.posix_process` when killing a process.
- Adding tests for the `tea.process` module.
- Process.is_running is now a property instead of a method
- Added abstract base class for the Process in the `tea.process` module,
now every platform specific implementation will conform to the interface of
the Process class
- Added list to `config` commander command, and fixed add to create a list
if it doesn't exist.
- Added a hack for positional arguments in commands.
- Adding safe and unsafe methods to the Config and MultiConfig classes. Safe
methods will never raise and error. They will either swallow the exception
or return a default value. Unsafe methods will raise either KeyError or
IndexError. (removed ConfigError)
- Removed the `execute_free*` functions. Nobody uses them, and actually
they are just confusing.


---