Add revision number

[kcthrn]

Just discovered this book. Would you be willing to add some sort of revision number to the html and pdf output?

A simple date of last update would work (yyyy-mm-dd).

[michaliskambi]

There is a date at the bottom of the HTML, https://castle-engine.io/modern_pascal_introduction.html . Right now Last updated 2021-05-24 16:36:34 +0200 .

It's not visible as plainly in PDF, but it is there too, in metadata. Click on PDF "Document Properties" or a similar option (depending on how you view PDF), and the date is there. Here's a screenshot how it looks in Firefox embedded PDF viewer.

You can also look at the GitHub history on https://github.com/michaliskambi/modern-pascal-introduction and https://github.com/michaliskambi/modern-pascal-introduction/commits/master , i.e. last commit date.