Add option to ignore converting certain figures

[timvink]

I have a feature request.

I would like the option to specify that some images in my page should not be converted to figures.

For example:

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Should render as:

But renders as:

Proposal

I would suggest two updates:

• If an image does not contain a caption (f.e. ![](<path>)), do not convert
• If an image caption contains the words img2fig-ignore, remove the text from the caption and do not convert to figure