Multiple prepend files

[SchrodingersGat]

• Allow prepending of multiple template files
• Refactor code to use parse_file() function

This PR adds the ability to provide multiple prepend files which is handy if you have multiple template files that you want to re-use across different projects.

Additionally it fixes a small bug where the program will error if the prepended file does not end with a newline

Example

Command

wireviz harness.yml --prepend-file input_a.yml input_b.yml

input_a.yml

templates:
  - &conn_a
    type: Connector A
    pn: CONN-A
    additional_components:
      - 
        type: Crimp A
        pn: CRIMP-A
        qty_multiplier: populated

input_b.yml

templates:
  - &conn_b
    type: Connector B
    pn: CONN-B
    additional_components:
      - 
        type: Crimp B
        pn: CRIMP-B
        qty_multiplier: populated

harness.yml

connectors:
  J1:
    <<: *conn_a
    pinlabels: [GND, POWER, SIGNAL]
    pincount: 3

  J2:
    <<: *conn_b
    pinlabels: [GND, SIGNAL, POWER]
    pincount: 3
  
cables:
  W1:
    gauge: 26 AWG
    wirecount: 8

connections:
  -
    - J1: [1-3]
    - W1: [1, 5, 8]
    - J2: [1, 3, 2]

Output File

[kvid]

Thank you for this contribution, @SchrodingersGat. I'm sorry that your PR has been unanswered until now. Several older PRs have just recently been merged into the dev branch (see #316 for a description), and it seems that code already supports multiple prepend files.

Please try the current dev branch, and compare it with your own implementation. If your new functionality is fully present in the current dev branch, then this PR is now obsolete, but if your contributions might have some extra advantages, then feel free to create a new PR for that, but please use dev (not master) as the PR base branch.

[SchrodingersGat]

@kvid thanks for the response. If this feature is now included, I'll close this out. Glad to see that wireviz is receiving some attention again :)