Feature python package main script

[chaps]

Adds support for installing as python package: enables installing from project root with: pip install ./ enables installing from remote source: e.g. pip install -U git+ssh://git@github.com/chaps/OrganiseDesktop.git@feature-python-package-main-script enables CLI command organise_desktop after installing enables calling GUI application from module : python -m organise_desktop after installing

• Adds init.py and main.py to treat organise_desktop dir as a python package.
• Moves setup.py to the root of the project, enables pip install ./ from the root of the project.
• Edits Cli.py import statements to import local modules from relative import.
• Wraps main function in Cli.py to enable console script.
• organise_desktop command added to entry_points for cli usage.
• Wraps Clean.py main function and imports it in main module

[KokoseiJ]

Reviewed. Perfect. I'm accepting this.