Added CLI Interface

[Viermusketiere]

I added a CLI interface which enables the plugin to be used standalone on an arbitrary board file.
Reason is that most other JLCPCB scripts available either require a schematic file (which in my case is not available).

No additional dependencies are added.
Changes to existing code have been kept to a bare minimum as the plugin functionality is the main feature.

CLI can simply be used by cloning the repository and running python -m plugins.cli -p [pathToBoardFile].
See python -m plugins.cli --help on how to set all options which are implemented in the GUI menu as command parameters.

python3 -m plugins.cli -h

usage: Fabrication Toolkit [-h] --path PATH [--additionalLayers ADDITIONALLAYERS] [--user1VCut] [--user2AltVCut] [--autoTransitions] [--autoFill] [--excludeDNP] [--openBrowser]

Generates JLCPCB production files from a KiCAD board file

options:
  -h, --help            show this help message and exit
  --path PATH, -p PATH  Path to KiCAD board file
  --additionalLayers ADDITIONALLAYERS, -aL ADDITIONALLAYERS  Additional layers(comma-separated)
  --user1VCut, -u1      Set User.1 as V-Cut layer
  --user2AltVCut, -u2   Use User.2 for alternative Edge-Cut layer
  --autoTransitions, -t    Apply automatic position/rotation translations
  --autoFill, -f        Apply automatic fill for all zones
  --excludeDNP, -e      Exclude DNP components from BOM
  --openBrowser, -b     Open webbrowser with directory file overview after generation

Feel free to make any suggestion on improvements.

[bennymeg]

Thank you for the contribution. Added a couple of suggestions.

[bennymeg]

In sake of completeness, would you mind adding also 'ALL_ACTIVE_LAYERS_OPT' option? It was added in a recent PR.

[bennymeg]

What do you think about moving this function to the utils module and make it generate the progress bar string instead of printing it. than it can be used in the progress function instead of nesting inside it.

[Viermusketiere]

I included your requested changes.
I kept the printing inside the 'print_cli_progress_bar' as custom parameters need to be specified to print and it is easier and cleaner to keep it together inside the function.
Also added documentation to the README for the feature

[bennymeg]

Thank you