Tikz image generation

[xfbs]

I'm currently using webgen for a personal project and I've really come to like it. I do feel that I could do a bit to improve the tikz support tho. So here's some questions/ideas:

• Why are you calling pdflatex with the -shell-escape flag? That would be a potential security issue.
• Would it make sense to add support for xelatex/lualatex? They natively support system fonts with fontspec.
• Would it make sense to use \documentclass[tikz]{standalone}, in datawebgen/passive_sources/templates/tikz.template, because like the you don't need pdfcrop and you get a lot of useful packages pre-loaded?
• Would it make sense to support generating *.svg images using pdf2svg from the Tikz drawings?

[gettalong]

Thanks for the issue and the pull requests - I just wanted to let you know that it will take some time for me to look at the things you propose but from a quick look-through they seem okay and valid.

[xfbs]

Hey, that's okay. I'm just contributing back the things I've tweaked on my end :)

[gettalong]

As for -shell-escape: I really don't know anymore :( But since webgen is normally run only locally it shouldn't be that much of a security problem.

I have integrated all your pull requests - thank you!