More refactoring for the python dependencies and some cleaning

- python class refactoring:
    - python\install.pp    -> installs python, pip and ez + path configuration
    - python\dependency.pp -> abstraction for python dependency.
    - nova_dependencies.pp -> refactoring and resources ordering
- extract_file command extracted to independent file in base/extract_file.pp
    - Contains 7zip installation
- download command now extracted to independent file in base/remote_file.pp
- commands.pp deleted, al relevant commands are now independent defines.
- init.pp: cleaning and referencing new nova_dependencies.
- removed some tools references: 7z (in extract now), gchrome, notpad, vcpp, vexa.