Replace xhtml2pdf dependency with WeasyPrint

[Ryan J Ollos]

The following was sent to me by a Debian packager:

The pisa Homepage (xhtml2pdf.com) redirects to sejda.com, the open source backend of that is at sejda.org but is now written in java.

The pisa PyPi page says it is replaced by xhtml2pdf. It looks like this is a rename of the pisa codebase.

​https://pypi.python.org/pypi/pisa/

The xhtml2pdf PyPi page says that it is !abandoned/dead and to use WeasyPrint instead.

​https://pypi.python.org/pypi/xhtml2pdf

That said, there are still some recentish commits:

​https://github.com/xhtml2pdf/xhtml2pdf/commits/master

It might be a good idea to add support for WeasyPrint to TracWikiPrintPlugin as it has had more recent commits:

​http://weasyprint.org/ ​https://github.com/Kozea/WeasyPrint ​https://github.com/Kozea/WeasyPrint/commits/master

[Cinc-th]

Wrt xhtml2pdf:

Last commit was not too long ago (7 month) and there is no notice (anymore ?) about abandoning the project: ​​https://pypi.python.org/pypi/xhtml2pdf

Problem with WeasyPrint is, it's Python 3 only, thus only for Trac >= 1.6 (whenever that will be released).