refactor: initialiser package

[gruzewski]

Follow up from #964

Proposed Changes

Small refactoring of the initialiser.py package. Changes:

• extracted generating a tree structure to a dedicated function
• changed a bit output of initialise_skeleton for better visibility (see "Testing" section below)

Testing:

• Manually ran kapitan init --directory multiple times

  State before each run:

   ➜  kapitan git:(master) tree /tmp/kapitan                                                                                                                                                            
   git:(master|)
   /tmp/kapitan
   ├── file_that_existed_before.txt
   └── this_existed_before
       └── file.txt
   
   2 directories, 2 files

  Old:

   ➜  kapitan git:(master) poetry run kapitan init --directory /tmp/kapitan                                                                                                                             git:(master|)
   creating /tmp/kapitan/components
   creating /tmp/kapitan/components/other_component
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/components/other_component/__init__.py -> /tmp/kapitan/components/other_component
   creating /tmp/kapitan/components/my_component
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/components/my_component/my_component.jsonnet -> /tmp/kapitan/components/my_component
   creating /tmp/kapitan/inventory
   creating /tmp/kapitan/inventory/targets
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/inventory/targets/my_target.yml -> /tmp/kapitan/inventory/targets
   creating /tmp/kapitan/inventory/classes
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/inventory/classes/common.yml -> /tmp/kapitan/inventory/classes
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/inventory/classes/my_component.yml -> /tmp/kapitan/inventory/classes
   creating /tmp/kapitan/templates
   creating /tmp/kapitan/templates/docs
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/templates/docs/my_readme.md -> /tmp/kapitan/templates/docs
   creating /tmp/kapitan/templates/scripts
   copying /Users/jacek/Code/kapitan/kapitan/inputs/templates/templates/scripts/my_script.sh -> /tmp/kapitan/templates/scripts
   Populated /tmp/kapitan with:
   components
       other_component
           __init__.py
       my_component
           my_component.jsonnet
   inventory
       targets
           my_target.yml
       classes
           common.yml
           my_component.yml
   templates
       docs
           my_readme.md
       scripts
           my_script.sh
  
   ➜  kapitan_fork git:(refactor_initialiser_package) ✗ poetry run kapitan init --directory /tmp/kapitan                                                       git:(refactor_initialiser_package|✚2…1
   Populated /tmp/kapitan with:

  New:

  ➜  kapitan_fork git:(refactor_initialiser_package) ✗ poetry run kapitan init --directory /tmp/kapitan                                                       git:(refactor_initialiser_package|✚2…1
  Populated /tmp/kapitan with:
  ├── components
  │   ├── other_component
  │   │   └── __init__.py
  │   └── my_component
  │       └── my_component.jsonnet
  ├── inventory
  │   ├── targets
  │   │   └── my_target.yml
  │   └── classes
  │       ├── common.yml
  │       └── my_component.yml
  └── templates
      ├── docs
      │   └── my_readme.md
      └── scripts
          └── my_script.sh
  
  ➜  kapitan_fork git:(refactor_initialiser_package) ✗ poetry run kapitan init --directory /tmp/kapitan                                                       git:(refactor_initialiser_package|✚2…1
  Populated /tmp/kapitan with:

[MatteoVoges]

Hey @gruzewski , The new output looks so much better!!! Thank you for that. Could you merge the pull request that belong to the init command (#966 and #964) into a single one to keep track of all the changes?
I think we can just use os.system("tree path/to/print") call to achieve a tree output of a directory. This would simplify this change so much, that no tests are needed.

[gruzewski]

Hey @gruzewski , The new output looks so much better!!! Thank you for that. Could you merge the pull request that belong to the init command (#966 and #964) into a single one to keep track of all the changes? I think we can just use os.system("tree path/to/print") call to achieve a tree output of a directory. This would simplify this change so much, that no tests are needed.

I can merge both, but it felt too big for review. Changes from #964 are showing because I used that branch as a base.

Regarding using os.system("tree path/to/print"), that is not feasible. tree is not installed by default on many OS (for instance, MacOS doesn't have it).

[MatteoVoges]

@gruzewski We could use find on macOS to get the files and output them as a tree. Another solution would be using package directory-tree.
I think if you remove or merge the changes regarding copy_tree and fix the tests we are good to go!