Now the assets are correcly installed along with the package

[Iximiel]

If you download the tar or the wheel from here: https://pypi.org/project/PlumedToHTML/0.99/#files, you will get the package without the asset directory

The asset/header.html file there is used by PlumedToHTML.get_html_header() and since is not packed is a guaranteed error.

With this PR that error is solved

With pip install . I get the check_inputs directory installed in the environment, but with python -m build . the created wheel contains only PlumedToHTML with the assets :)

So I think this is a good improvement

[Iximiel]

With pip install . I get the check_inputs directory installed in the environment

A solution could be to be more canonical and change from the bare PlumedToHTML dir in the wild

.
├── check_inputs
│   ├── create_inputs.py
│   └── make_inputs.sh
├── LICENSE
├── PlumedToHTML
│   ├── assets
│   │   └── header.html
│   ├── __init__.py
│   ├── PlumedFormatter.py
│   ├── PlumedLexer.py
│   ├── PlumedToHTML.py
│   └── tests
│       ├── test_code.py
│       ├── test_formatter.py
│       ├── test_lexer.py
│       ├── test_markdown.py
│       └── test_mermaid.py
├── README.md
├── setup.py
├── tdata
│   ├── Distance2.cpp
│   ├── formattests.json
│   ├── groups.dat
│   ├── helix.pdb
│   ├── lexertests.json
│   ├── other.0.inc
│   ├── other.1.inc
│   ├── recursive.inc
│   ├── solution.dat
│   ├── testInclude.inc
│   └── tests.json
└── tox.ini

to protect the PlumedToHTML dir within src like this:

.
├── check_inputs
│   ├── create_inputs.py
│   └── make_inputs.sh
├── LICENSE
├── README.md
├── setup.py
├── src
│   └── PlumedToHTML
│       ├── assets
│       │   └── header.html
│       ├── __init__.py
│       ├── PlumedFormatter.py
│       ├── PlumedLexer.py
│       ├── PlumedToHTML.py
│       └── tests
│           ├── test_code.py
│           ├── test_formatter.py
│           ├── test_lexer.py
│           ├── test_markdown.py
│           └── test_mermaid.py
├── tdata
│   ├── Distance2.cpp
│   ├── formattests.json
│   ├── groups.dat
│   ├── helix.pdb
│   ├── lexertests.json
│   ├── other.0.inc
│   ├── other.1.inc
│   ├── recursive.inc
│   ├── solution.dat
│   ├── testInclude.inc
│   └── tests.json
└── tox.ini